diff --git a/src/main/java/com/example/spot/api/code/status/ErrorStatus.java b/src/main/java/com/example/spot/api/code/status/ErrorStatus.java
index 6539787b..07b051d3 100644
--- a/src/main/java/com/example/spot/api/code/status/ErrorStatus.java
+++ b/src/main/java/com/example/spot/api/code/status/ErrorStatus.java
@@ -28,6 +28,7 @@ public enum ErrorStatus implements BaseErrorCode {
     _TERMS_NOT_AGREED(HttpStatus.FORBIDDEN, "COMMON4013", "이용 약관이 동의되지 않았습니다."),
     _MEMBER_EMAIL_EXIST(HttpStatus.BAD_REQUEST, "COMMON4014", "이미 가입 된 이메일입니다. 다른 로그인 방식을 이용해주세요."),
     _RSA_ERROR(HttpStatus.BAD_REQUEST, "COMMON4015", "RSA 에러가 발생했습니다."),
+    _NOT_ADMIN(HttpStatus.FORBIDDEN, "COMMON4016", "관리자 권한이 없습니다."),
 
     // 네이버 소셜 로그인 관련 에러
     _NAVER_SIGN_IN_INTEGRATION_FAILED(HttpStatus.UNAUTHORIZED, "NAVER4001", "네이버 로그인 연동에 실패하였습니다."),
@@ -63,8 +64,10 @@ public enum ErrorStatus implements BaseErrorCode {
     _STUDY_OWNER_NOT_FOUND(HttpStatus.NOT_FOUND, "STUDY4002", "스터디장을 찾을 수 없습니다."),
     _STUDY_ALREADY_APPLIED(HttpStatus.BAD_REQUEST, "STUDY4003", "이미 신청된 스터디입니다."),
     _STUDY_MEMBER_NOT_FOUND(HttpStatus.NOT_FOUND, "STUDY4004", "스터디 회원을 찾을 수 없습니다."),
+    _STUDY_MEMBER_NOT_EXIST(HttpStatus.NOT_FOUND, "STUDY4008", "스터디 회원이 아닙니다."),
     _STUDY_NOT_APPROVED(HttpStatus.FORBIDDEN, "STUDY4005", "승인되지 않은 스터디입니다."),
     _STUDY_OWNER_CANNOT_WITHDRAW(HttpStatus.FORBIDDEN, "STUDY4006", "스터디장은 스터디를 탈퇴할 수 없습니다."),
+    _STUDY_OWNER_ONLY_CAN_WITHDRAW(HttpStatus.FORBIDDEN, "STUDY4007", "스터디장만 해당 API를 통해 스터디를 탈퇴할 수 있습니다."),
     _STUDY_NOT_RECRUITING(HttpStatus.BAD_REQUEST, "STUDY4007", "스터디 모집기한이 아닙니다."),
     _STUDY_APPLICANT_NOT_FOUND(HttpStatus.NOT_FOUND, "STUDY4009", "처리를 기다리는 스터디 신청을 찾을 수 없습니다."),
     _STUDY_APPLY_ALREADY_PROCESSED(HttpStatus.BAD_REQUEST, "STUDY4010","스터디 신청이 이미 처리된 회원입니다."),
@@ -77,6 +80,7 @@ public enum ErrorStatus implements BaseErrorCode {
     _ALREADY_STUDY_MEMBER(HttpStatus.BAD_REQUEST, "STUDY4017", "이미 스터디 멤버입니다."),
     _STUDY_OWNER_ONLY_CAN_TERMINATE(HttpStatus.BAD_REQUEST, "STUDY4018", "스터디장만 스터디를 종료할 수 있습니다."),
     _STUDY_ALREADY_TERMINATED(HttpStatus.BAD_REQUEST, "STUDY4019", "이미 종료된 스터디입니다."),
+    _OWNED_STUDY_EXISTS(HttpStatus.BAD_REQUEST, "STUDY4020", "운영중인 스터디가 존재합니다."),
 
     //스터디 게시글 관련 에러
     _STUDY_POST_NOT_FOUND(HttpStatus.NOT_FOUND, "POST4001", "스터디 게시글을 찾을 수 없습니다."),
diff --git a/src/main/java/com/example/spot/api/code/status/SuccessStatus.java b/src/main/java/com/example/spot/api/code/status/SuccessStatus.java
index b606afd3..d294cea6 100644
--- a/src/main/java/com/example/spot/api/code/status/SuccessStatus.java
+++ b/src/main/java/com/example/spot/api/code/status/SuccessStatus.java
@@ -69,6 +69,7 @@ public enum SuccessStatus implements BaseCode {
     _STUDY_APPLICANT_UPDATED(HttpStatus.OK, "STUDY4011", "스터디 신청 처리 완료"),
     _STUDY_APPLY_COMPLETED(HttpStatus.OK, "STUDY4012", "스터디 신청 완료"),
     _HOT_KEYWORD_FOUND(HttpStatus.OK, "SEARCH2001", "인기 검색어 조회 완료"),
+    _STUDY_HOST_FOUND(HttpStatus.OK, "STUDY2013", "스터디 호스트 조회 완료"),
 
     //스터디 출석 퀴즈 관련
     _STUDY_QUIZ_CREATED(HttpStatus.CREATED, "QUIZ2001", "스터디 퀴즈 생성 완료"),
diff --git a/src/main/java/com/example/spot/config/WebSecurity.java b/src/main/java/com/example/spot/config/WebSecurity.java
index 0c9956e2..5bae53a3 100644
--- a/src/main/java/com/example/spot/config/WebSecurity.java
+++ b/src/main/java/com/example/spot/config/WebSecurity.java
@@ -62,7 +62,7 @@ protected SecurityFilterChain configure(HttpSecurity http) throws Exception {
                         .requestMatchers(new AntPathRequestMatcher("/spot/login/kakao", "GET")).permitAll()
                         .requestMatchers(new AntPathRequestMatcher("/spot/members/sign-in/kakao", "GET")).permitAll()
                         .requestMatchers(new AntPathRequestMatcher("/spot/members/sign-in/kakao/redirect", "GET")).permitAll()
-                        .requestMatchers(new AntPathRequestMatcher("/spot/member/test", "POST")).permitAll()
+                        .requestMatchers(new AntPathRequestMatcher("/spot/members/test", "POST")).permitAll()
                         .requestMatchers(new AntPathRequestMatcher("/spot/current-env", "GET")).permitAll()
                         .requestMatchers(new AntPathRequestMatcher("/api-docs")).permitAll()
                         .requestMatchers(new AntPathRequestMatcher("/v3/**", "GET")).permitAll()
diff --git a/src/main/java/com/example/spot/domain/Member.java b/src/main/java/com/example/spot/domain/Member.java
index 33480b8e..6db120ad 100644
--- a/src/main/java/com/example/spot/domain/Member.java
+++ b/src/main/java/com/example/spot/domain/Member.java
@@ -62,7 +62,7 @@ public class Member extends BaseEntity {
     private Carrier carrier;
 
     // 안 쓰면 지워도 될 것 같은데 사이드 이펙트 생길까봐 일단 놔둡니다..!
-    @Column(length = 15, unique = true)
+    @Column(length = 15)
     private String phone;
 
     @Column(nullable = false)
@@ -75,6 +75,7 @@ public class Member extends BaseEntity {
     @Column(nullable = false)
     private String profileImage;
 
+    @Setter
     @Column
     private LocalDateTime inactive;
 
@@ -95,12 +96,12 @@ public class Member extends BaseEntity {
     private Status status;
 
     //== 스터디 희망사유 ==//
-    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL)
+    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL, orphanRemoval = true)
     @Builder.Default
     private List<StudyReason> studyReasonList = new ArrayList<>();
 
     //== 알림 ==//
-    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL)
+    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL, orphanRemoval = true)
     @Builder.Default
     private List<Notification> notificationList = new ArrayList<>();
 
@@ -110,106 +111,106 @@ public class Member extends BaseEntity {
     private List<MemberReport> memberReportList = new ArrayList<>();
 
     //== 회원이 선호하는 테마 ==//
-    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL)
+    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL, orphanRemoval = true)
     @Builder.Default
     private List<MemberTheme> memberThemeList = new ArrayList<>();
 
     //== 회원의 출석 목록 ==//
-    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL)
+    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL, orphanRemoval = true)
     @Builder.Default
     private List<MemberAttendance> memberAttendanceList = new ArrayList<>();
 
     //== 회원이 참여하는 스터디 목록 ==//
-    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL)
+    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL, orphanRemoval = true)
     @Builder.Default
     private List<MemberStudy> memberStudyList = new ArrayList<>();
 
     //== 회원이 찜한 스터디 목록 ==//
-    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL)
+    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL, orphanRemoval = true)
     @Builder.Default
     private List<PreferredStudy> preferredStudyList = new ArrayList<>();
 
     //== 회원이 선호하는 지역 목록 ==//
-    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL)
+    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL, orphanRemoval = true)
     @Builder.Default
     private List<PreferredRegion> preferredRegionList = new ArrayList<>();
 
    ////== 회원이 작성한 게시글 목록 ==//
-   @OneToMany(mappedBy = "member", cascade = CascadeType.ALL)
+   @OneToMany(mappedBy = "member", cascade = CascadeType.ALL, orphanRemoval = true)
    @Builder.Default
    private List<Post> postList = new ArrayList<>();
 
    ////== 회원이 좋아요한 게시글 목록 ==//
-   @OneToMany(mappedBy = "member", cascade = CascadeType.ALL)
+   @OneToMany(mappedBy = "member", cascade = CascadeType.ALL, orphanRemoval = true)
    @Builder.Default
    private List<LikedPost> likedPostList = new ArrayList<>();
 
    ////== 회원이 선호하는 지역 목록 ==//
-   @OneToMany(mappedBy = "member", cascade = CascadeType.ALL)
+   @OneToMany(mappedBy = "member", cascade = CascadeType.ALL, orphanRemoval = true)
    @Builder.Default
    private List<PostReport> postReportList = new ArrayList<>();
 
    ////== 회원이 스크랩한 게시글 목록 ==//
-   @OneToMany(mappedBy = "member", cascade = CascadeType.ALL)
+   @OneToMany(mappedBy = "member", cascade = CascadeType.ALL, orphanRemoval = true)
    @Builder.Default
    private List<MemberScrap> memberScrapList = new ArrayList<>();
 
    ////== 회원이 작성한 게시글 댓글 목록 ==//
-   @OneToMany(mappedBy = "member", cascade = CascadeType.ALL)
+   @OneToMany(mappedBy = "member", cascade = CascadeType.ALL, orphanRemoval = true)
    @Builder.Default
    private List<PostComment> postCommentList = new ArrayList<>();
 
    ////== 회원이 좋아요한 게시글 댓글 목록 ==//
-   @OneToMany(mappedBy = "member", cascade = CascadeType.ALL)
+   @OneToMany(mappedBy = "member", cascade = CascadeType.ALL, orphanRemoval = true)
    @Builder.Default
    private List<LikedPostComment> likedCommentList = new ArrayList<>();
 
     //== 회원이 작성한 스터디 게시글 목록 ==//
-    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL)
+    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL, orphanRemoval = true)
     @Builder.Default
     private List<StudyPost> studyPostList = new ArrayList<>();
 
     //== 회원이 좋아요한 스터디 게시글 목록 ==//
-    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL)
+    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL, orphanRemoval = true)
     @Builder.Default
     private List<StudyLikedPost> studyLikedPostList = new ArrayList<>();
 
     //== 회원이 작성한 스터디 게시글 댓글 목록 ==//
-    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL)
+    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL, orphanRemoval = true)
     @Builder.Default
     private List<StudyPostComment> studyPostCommentList = new ArrayList<>();
 
     //== 회원이 좋아요한 게시글 댓글 목록 ==//
-    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL)
+    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL, orphanRemoval = true)
     @Builder.Default
     private List<StudyLikedComment> studyLikedCommentList = new ArrayList<>();
 
     //== 회원이 생성한 투표 목록 ==//
-    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL)
+    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL, orphanRemoval = true)
     @Builder.Default
     private List<Vote> voteList = new ArrayList<>();
 
     //== 회원이 투표한 항목 목록 ==//
-    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL)
+    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL, orphanRemoval = true)
     @Builder.Default
     private List<MemberVote> memberVoteList = new ArrayList<>();
 
     //== 회원이 선호하는 지역 목록 ==//
-    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL)
+    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL, orphanRemoval = true)
     @Builder.Default
     private List<PreferredRegion> regions = new ArrayList<>();
 
     //== 회원이 생성한 스터디 퀴즈 목록 ==//
-    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL)
+    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL, orphanRemoval = true)
     @Builder.Default
     private List<Quiz> quizList = new ArrayList<>();
 
     //== 회원이 생성한 스터디 일정 목록 ==//
-    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL)
+    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL, orphanRemoval = true)
     @Builder.Default
     private List<Schedule> scheduleList = new ArrayList<>();
 
-    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL)
+    @OneToMany(mappedBy = "member", cascade = CascadeType.ALL, orphanRemoval = true)
     @Builder.Default
     private List<ToDoList> toDoLists = new ArrayList<>();
 
diff --git a/src/main/java/com/example/spot/domain/Region.java b/src/main/java/com/example/spot/domain/Region.java
index 34168b2e..b746c51b 100644
--- a/src/main/java/com/example/spot/domain/Region.java
+++ b/src/main/java/com/example/spot/domain/Region.java
@@ -32,11 +32,11 @@ public class Region extends BaseEntity {
     private String neighborhood;
 
     @Builder.Default
-    @OneToMany(mappedBy = "region")
+    @OneToMany(mappedBy = "region", cascade = CascadeType.ALL)
     private List<RegionStudy> regionStudyList = new ArrayList<>();
 
     @Builder.Default
-    @OneToMany(mappedBy = "region")
+    @OneToMany(mappedBy = "region", cascade = CascadeType.ALL)
     private List<PreferredRegion> prefferedRegionList = new ArrayList<>();
 
 
diff --git a/src/main/java/com/example/spot/domain/mapping/MemberStudy.java b/src/main/java/com/example/spot/domain/mapping/MemberStudy.java
index 11ed76b1..5358a246 100644
--- a/src/main/java/com/example/spot/domain/mapping/MemberStudy.java
+++ b/src/main/java/com/example/spot/domain/mapping/MemberStudy.java
@@ -27,11 +27,17 @@ public class MemberStudy extends BaseEntity {
     private ApplicationStatus status;
 
     @Column(nullable = false, columnDefinition = "BIT DEFAULT 0")
+    @Setter
     private Boolean isOwned;
 
     @Column(columnDefinition = "text")
     private String introduction;
 
+    // 해당 유저로 호스트를 위임하는 이유
+    @Column(columnDefinition = "text")
+    @Setter
+    private String reason;
+
     //== 회원 ==//
     @Setter
     @ManyToOne(fetch = FetchType.LAZY)
diff --git a/src/main/java/com/example/spot/domain/study/Study.java b/src/main/java/com/example/spot/domain/study/Study.java
index cf5f61aa..36293b07 100644
--- a/src/main/java/com/example/spot/domain/study/Study.java
+++ b/src/main/java/com/example/spot/domain/study/Study.java
@@ -59,6 +59,9 @@ public class Study extends BaseEntity {
     @Enumerated(EnumType.STRING)
     private StudyState studyState;
 
+    @Column(length = 30)
+    private String performance;
+
     @Column(nullable = false)
     private Boolean isOnline;
 
@@ -74,7 +77,6 @@ public class Study extends BaseEntity {
     @Column(nullable = false)
     private String title;
 
-    @Setter
     @Column(nullable = false)
     @Enumerated(EnumType.STRING)
     private Status status;
@@ -199,4 +201,10 @@ public void deleteVote(Vote vote) {
     public void addToDoList(ToDoList toDoList) {
         toDoLists.add(toDoList);
     }
+
+    public void terminateStudy(String performance) {
+        this.studyState = StudyState.COMPLETED;
+        this.status = Status.OFF;
+        this.performance = performance;
+    }
 }
diff --git a/src/main/java/com/example/spot/repository/MemberRepository.java b/src/main/java/com/example/spot/repository/MemberRepository.java
index db835538..c1f8fea2 100644
--- a/src/main/java/com/example/spot/repository/MemberRepository.java
+++ b/src/main/java/com/example/spot/repository/MemberRepository.java
@@ -1,6 +1,9 @@
 package com.example.spot.repository;
 
 import com.example.spot.domain.Member;
+
+import java.time.LocalDateTime;
+import java.util.List;
 import java.util.Optional;
 
 import com.example.spot.domain.enums.LoginType;
@@ -23,4 +26,6 @@ public interface MemberRepository extends JpaRepository<Member, Long> {
     boolean existsByEmailAndLoginType(String email, LoginType loginType);
 
     Optional<Member> findByEmailAndLoginType(String email, LoginType loginType);
+
+    List<Member> findAllByInactiveBefore(LocalDateTime stdTime);
 }
diff --git a/src/main/java/com/example/spot/repository/MemberStudyRepository.java b/src/main/java/com/example/spot/repository/MemberStudyRepository.java
index 9c28aa61..898be448 100644
--- a/src/main/java/com/example/spot/repository/MemberStudyRepository.java
+++ b/src/main/java/com/example/spot/repository/MemberStudyRepository.java
@@ -1,5 +1,6 @@
 package com.example.spot.repository;
 
+import com.example.spot.domain.Member;
 import com.example.spot.domain.enums.ApplicationStatus;
 import com.example.spot.domain.mapping.MemberStudy;
 import org.springframework.data.domain.Pageable;
@@ -30,4 +31,7 @@ public interface MemberStudyRepository extends JpaRepository<MemberStudy, Long>
 
     boolean existsByMemberIdAndStudyIdAndStatus(Long memberId, Long studyId, ApplicationStatus applicationStatus);
 
+    Optional<MemberStudy> findByStudyIdAndIsOwned(Long studyId, boolean b);
+
+    boolean existsByMemberIdAndIsOwned(Long memberId, boolean b);
 }
diff --git a/src/main/java/com/example/spot/repository/RefreshTokenRepository.java b/src/main/java/com/example/spot/repository/RefreshTokenRepository.java
index 5039aaed..8ffd3cc2 100644
--- a/src/main/java/com/example/spot/repository/RefreshTokenRepository.java
+++ b/src/main/java/com/example/spot/repository/RefreshTokenRepository.java
@@ -2,6 +2,8 @@
 
 import com.example.spot.domain.auth.RefreshToken;
 import com.example.spot.domain.study.Option;
+
+import java.util.List;
 import java.util.Optional;
 import org.springframework.data.jpa.repository.JpaRepository;
 import org.springframework.stereotype.Repository;
@@ -13,4 +15,6 @@ public interface RefreshTokenRepository extends JpaRepository<RefreshToken, Long
     void deleteAllByMemberId(Long memberId);
 
     boolean existsByMemberId(Long memberId);
+
+    void deleteAllByMemberIdIn(List<Long> deletedMemberIds);
 }
diff --git a/src/main/java/com/example/spot/scheduler/MemberRemovalScheduler.java b/src/main/java/com/example/spot/scheduler/MemberRemovalScheduler.java
new file mode 100644
index 00000000..34512e50
--- /dev/null
+++ b/src/main/java/com/example/spot/scheduler/MemberRemovalScheduler.java
@@ -0,0 +1,28 @@
+package com.example.spot.scheduler;
+
+import com.example.spot.service.admin.AdminService;
+import com.example.spot.web.dto.admin.AdminResponseDTO;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.scheduling.annotation.Scheduled;
+import org.springframework.stereotype.Component;
+import org.springframework.transaction.annotation.Transactional;
+
+@Component
+@Slf4j
+@RequiredArgsConstructor
+@Transactional
+public class MemberRemovalScheduler {
+
+    private final AdminService adminService;
+
+    // 매일 오전 6시에 탈퇴 후 30일이 지난 회원을 삭제합니다.
+    @Scheduled(cron = "0 0 6 * * *")
+    public void deleteMembers() {
+        AdminResponseDTO.DeletedMemberListDTO deletedMemberListDTO = adminService.deleteInactiveMembers();
+        log.info("Deleted Members:  {}", deletedMemberListDTO.getDeletedMembers().size());
+        deletedMemberListDTO.getDeletedMembers().forEach(member ->
+                log.info("Deleted Member: id={}, email={}", member.getMemberId(), member.getEmail())
+        );
+    }
+}
diff --git a/src/main/java/com/example/spot/security/utils/SecurityUtils.java b/src/main/java/com/example/spot/security/utils/SecurityUtils.java
index 50e0db9c..4e861fd0 100644
--- a/src/main/java/com/example/spot/security/utils/SecurityUtils.java
+++ b/src/main/java/com/example/spot/security/utils/SecurityUtils.java
@@ -64,4 +64,13 @@ public static String getVerifiedTempUserEmail() {
         }
         return authentication.getName();
     }
+
+    /**
+     * 현재 인증된 사용자의 로그인 정보를 삭제합니다.
+     * 로그인 정보를 삭제하며 SecurityContext도 함께 삭제합니다.
+     */
+    public static void deleteCurrentUser() {
+        SecurityContextHolder.getContext().setAuthentication(null);
+        SecurityContextHolder.clearContext();
+    }
 }
diff --git a/src/main/java/com/example/spot/service/admin/AdminService.java b/src/main/java/com/example/spot/service/admin/AdminService.java
new file mode 100644
index 00000000..53efeffd
--- /dev/null
+++ b/src/main/java/com/example/spot/service/admin/AdminService.java
@@ -0,0 +1,15 @@
+package com.example.spot.service.admin;
+
+import com.example.spot.web.dto.admin.AdminResponseDTO;
+
+public interface AdminService {
+
+/* ----------------------------- 회원 정보 관리 API ------------------------------------- */
+
+    boolean getIsAdmin();
+
+    AdminResponseDTO.DeletedMemberListDTO deleteInactiveMembers();
+
+/* ----------------------------- 신고 내역 관리 API ------------------------------------- */
+
+}
diff --git a/src/main/java/com/example/spot/service/admin/AdminServiceImpl.java b/src/main/java/com/example/spot/service/admin/AdminServiceImpl.java
new file mode 100644
index 00000000..c933594b
--- /dev/null
+++ b/src/main/java/com/example/spot/service/admin/AdminServiceImpl.java
@@ -0,0 +1,57 @@
+package com.example.spot.service.admin;
+
+import com.example.spot.api.code.status.ErrorStatus;
+import com.example.spot.api.exception.handler.MemberHandler;
+import com.example.spot.domain.Member;
+import com.example.spot.repository.MemberRepository;
+import com.example.spot.repository.RefreshTokenRepository;
+import com.example.spot.security.utils.SecurityUtils;
+import com.example.spot.web.dto.admin.AdminResponseDTO;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.time.LocalDateTime;
+import java.util.List;
+
+@Service
+@RequiredArgsConstructor
+@Transactional
+public class AdminServiceImpl implements AdminService {
+
+    private final MemberRepository memberRepository;
+    private final RefreshTokenRepository refreshTokenRepository;
+
+/* ----------------------------- 회원 정보 관리 API ------------------------------------- */
+
+    @Override
+    public boolean getIsAdmin() {
+        Long memberId = SecurityUtils.getCurrentUserId();
+        Member member = memberRepository.findById(memberId)
+                .orElseThrow(() -> new MemberHandler(ErrorStatus._MEMBER_NOT_FOUND));
+        return member.getIsAdmin();
+    }
+
+    @Override
+    public AdminResponseDTO.DeletedMemberListDTO deleteInactiveMembers() {
+
+        // 삭제 기준일시
+        LocalDateTime stdTime = LocalDateTime.now().minusDays(30);
+
+        // 회원 삭제
+        List<Member> deletedMembers = memberRepository.findAllByInactiveBefore(stdTime);
+        List<Long> deletedMemberIds = deletedMembers.stream().map(Member::getId).toList();
+        AdminResponseDTO.DeletedMemberListDTO deletedMemberListDTO = AdminResponseDTO.DeletedMemberListDTO.toDTO(deletedMembers);
+
+        // Token 정리
+        refreshTokenRepository.deleteAllByMemberIdIn(deletedMemberIds);
+
+        // 회원 정보 정리
+        memberRepository.deleteAllByIdInBatch(deletedMemberIds);
+
+        return deletedMemberListDTO;
+    }
+
+/* ----------------------------- 신고 내역 관리 API ------------------------------------- */
+
+}
diff --git a/src/main/java/com/example/spot/service/auth/AuthService.java b/src/main/java/com/example/spot/service/auth/AuthService.java
index 57539b1e..6182153b 100644
--- a/src/main/java/com/example/spot/service/auth/AuthService.java
+++ b/src/main/java/com/example/spot/service/auth/AuthService.java
@@ -18,6 +18,8 @@ public interface AuthService {
 
     MemberResponseDTO.MemberInfoCreationDTO signUpAndPartialUpdate(String nickname, Boolean personalInfo, Boolean idInfo);
 
+    MemberResponseDTO.InactiveMemberDTO withdraw();
+
     void authorizeWithNaver(HttpServletRequest request, HttpServletResponse response);
 
     SocialLoginSignInDTO signInWithNaver(HttpServletRequest request, HttpServletResponse response, NaverCallback naverCallback) throws Exception;
@@ -41,5 +43,4 @@ public interface AuthService {
     MemberResponseDTO.AvailabilityDTO checkLoginIdAvailability(String loginId);
 
     MemberResponseDTO.AvailabilityDTO checkEmailAvailability(String email);
-
 }
diff --git a/src/main/java/com/example/spot/service/auth/AuthServiceImpl.java b/src/main/java/com/example/spot/service/auth/AuthServiceImpl.java
index c1993b3a..54e2c0de 100644
--- a/src/main/java/com/example/spot/service/auth/AuthServiceImpl.java
+++ b/src/main/java/com/example/spot/service/auth/AuthServiceImpl.java
@@ -6,6 +6,7 @@
 import com.example.spot.api.exception.handler.MemberHandler;
 import com.example.spot.domain.Member;
 import com.example.spot.domain.auth.RsaKey;
+import com.example.spot.repository.MemberStudyRepository;
 import com.example.spot.web.dto.rsa.Rsa;
 import com.example.spot.domain.auth.RefreshToken;
 import com.example.spot.domain.auth.VerificationCode;
@@ -43,6 +44,8 @@
 import java.util.stream.Collectors;
 import java.util.stream.IntStream;
 
+import jakarta.persistence.EntityManager;
+import jakarta.persistence.PersistenceContext;
 import jakarta.servlet.http.HttpServletRequest;
 import jakarta.servlet.http.HttpServletResponse;
 import lombok.RequiredArgsConstructor;
@@ -55,10 +58,15 @@
 @Transactional
 public class AuthServiceImpl implements AuthService{
 
+    @PersistenceContext
+    private EntityManager entityManager;
+
     private final JwtTokenProvider jwtTokenProvider;
     private final MemberRepository memberRepository;
+    private final MemberStudyRepository memberStudyRepository;
     private final RefreshTokenRepository refreshTokenRepository;
     private final VerificationCodeRepository verificationCodeRepository;
+
     private final MailService mailService;
     private final NaverOAuthService naverOAuthService;
 
@@ -135,6 +143,31 @@ public MemberResponseDTO.MemberInfoCreationDTO signUpAndPartialUpdate(String nic
         return MemberResponseDTO.MemberInfoCreationDTO.toDTO(member);
     }
 
+    @Override
+    public MemberResponseDTO.InactiveMemberDTO withdraw() {
+
+        // Authorization
+        Long memberId = SecurityUtils.getCurrentUserId();
+        Member member = memberRepository.findById(memberId)
+                .orElseThrow(() -> new MemberHandler(ErrorStatus._MEMBER_NOT_FOUND));
+
+        // 운영중인 스터디가 있는 경우 탈퇴 불가
+        if (memberStudyRepository.existsByMemberIdAndIsOwned(memberId, true)) {
+            throw new MemberHandler(ErrorStatus._OWNED_STUDY_EXISTS);
+        }
+
+        // inactive 필드 활성화
+        member.setInactive(LocalDateTime.now());
+
+        // SecurityContextHolder 정리
+        SecurityUtils.deleteCurrentUser();
+
+        // Refresh Token 정리
+        refreshTokenRepository.deleteAllByMemberId(memberId);
+
+        return MemberResponseDTO.InactiveMemberDTO.toDTO(member);
+    }
+
 /* ----------------------------- 네이버 소셜로그인 API ------------------------------------- */
 
     /**
@@ -191,13 +224,38 @@ public SocialLoginSignInDTO signInWithNaver(HttpServletRequest request, HttpServ
     private SocialLoginSignInDTO getSocialLoginSignInDTO(NaverMember.ResponseDTO responseDTO) {
         String email = responseDTO.getResponse().getEmail();
 
-        if (memberRepository.existsByEmailAndLoginTypeNot(email, LoginType.NAVER))
-            throw new GeneralException(ErrorStatus._MEMBER_EMAIL_EXIST);
+        // 다른 로그인 방식을 사용한 계정이 있는지 확인
+        if (memberRepository.existsByEmailAndLoginTypeNot(email, LoginType.NAVER)) {
+            Member member = memberRepository.findByEmail(email)
+                    .orElseThrow(() -> new MemberHandler(ErrorStatus._MEMBER_NOT_FOUND));
+
+            // 탈퇴한(inactive) 회원이면 기존 정보 삭제
+            if (member.getInactive() != null) {
+                refreshTokenRepository.deleteByMemberId(member.getId());
+                memberRepository.deleteById(member.getId());
+                entityManager.flush();
+            }
+            else {
+                throw new MemberHandler(ErrorStatus._MEMBER_EMAIL_ALREADY_EXISTS);
+            }
+        }
 
+        // 네이버 로그인 계정이 있는지 확인
         Boolean isSpotMember = Boolean.TRUE;
-
-        // 가입되지 않은 회원이면 회원 정보 저장
-        if (!memberRepository.existsByEmailAndLoginType(email, LoginType.NAVER)) {
+        if (memberRepository.existsByEmailAndLoginType(email, LoginType.NAVER)) {
+            Member member = memberRepository.findByEmail(email)
+                    .orElseThrow(() -> new MemberHandler(ErrorStatus._MEMBER_NOT_FOUND));
+
+            // 탈퇴한(inactive) 회원이면 기존 정보 삭제 후 회원 정보 저장
+            if (member.getInactive() != null) {
+                refreshTokenRepository.deleteByMemberId(member.getId());
+                memberRepository.deleteById(member.getId());
+                entityManager.flush();
+                isSpotMember = Boolean.FALSE;
+                signUpWithNaver(responseDTO);
+            }
+        }
+        else {
             isSpotMember = Boolean.FALSE;
             signUpWithNaver(responseDTO);
         }
@@ -277,6 +335,11 @@ public MemberResponseDTO.MemberSignInDTO signIn(Long rsaId, MemberRequestDTO.Sig
         Member member = memberRepository.findByLoginId(signInDTO.getLoginId())
                 .orElseThrow(() -> new MemberHandler(ErrorStatus._MEMBER_NOT_FOUND));
 
+        // 탈퇴한 회원이면 로그인 불가
+        if (member.getInactive() != null) {
+            throw new MemberHandler(ErrorStatus._MEMBER_NOT_FOUND);
+        }
+
         // 비밀번호 확인
         String password = getDecryptedPassword(rsaId, signInDTO.getPassword());
         if (!password.equals(member.getPassword())) {
@@ -396,14 +459,24 @@ public TokenResponseDTO.TempTokenDTO verifyEmail(String code, String email) {
     @Override
     public MemberResponseDTO.MemberSignInDTO signUp(Long rsaId, MemberRequestDTO.SignUpDTO signUpDTO) throws Exception {
 
-        // 회원 생성
+        // 이미 존재하는 회원인 경우
         if (memberRepository.existsByEmail(signUpDTO.getEmail())) {
-            throw new MemberHandler(ErrorStatus._MEMBER_EMAIL_ALREADY_EXISTS);
-        }
-        if (memberRepository.existsByLoginId(signUpDTO.getLoginId())) {
-            throw new MemberHandler(ErrorStatus._MEMBER_LOGIN_ID_ALREADY_EXISTS);
+
+            Member member = memberRepository.findByEmail(signUpDTO.getEmail())
+                    .orElseThrow(() -> new MemberHandler(ErrorStatus._MEMBER_NOT_FOUND));
+
+            // 탈퇴한(inactive) 회원이면 기존 정보 삭제 후 회원 생성
+            if (member.getInactive() != null) {
+                refreshTokenRepository.deleteByMemberId(member.getId());
+                memberRepository.deleteById(member.getId());
+                entityManager.flush();
+            }
+            else {
+                throw new MemberHandler(ErrorStatus._MEMBER_EMAIL_ALREADY_EXISTS);
+            }
         }
 
+        // 회원 생성
         String password = getDecryptedPassword(rsaId, signUpDTO.getPassword());
         String pwCheck = getDecryptedPassword(rsaId, signUpDTO.getPwCheck());
         if (!password.equals(pwCheck)) {
@@ -488,6 +561,11 @@ public MemberResponseDTO.FindIdDTO findId() {
         Member member = memberRepository.findByEmail(email)
                 .orElseThrow(() -> new MemberHandler(ErrorStatus._MEMBER_NOT_FOUND));
 
+        // 탈퇴한 회원이면 아이디 찾기 불가
+        if (member.getInactive() != null) {
+            throw new MemberHandler(ErrorStatus._MEMBER_NOT_FOUND);
+        }
+
         return MemberResponseDTO.FindIdDTO.toDTO(member);
     }
 
@@ -506,6 +584,11 @@ public MemberResponseDTO.FindPwDTO findPw(String loginId) {
         Member member = memberRepository.findByEmail(email)
                 .orElseThrow(() -> new MemberHandler(ErrorStatus._MEMBER_NOT_FOUND));
 
+        // 탈퇴한 회원이면 아이디 찾기 불가
+        if (member.getInactive() != null) {
+            throw new MemberHandler(ErrorStatus._MEMBER_NOT_FOUND);
+        }
+
         // 인증된 사용자의 아이디와 입력 아이디 일치 여부 확인
         if (!member.getLoginId().equals(loginId)) {
             throw new MemberHandler(ErrorStatus._MEMBER_NOT_FOUND);
diff --git a/src/main/java/com/example/spot/service/member/MemberServiceImpl.java b/src/main/java/com/example/spot/service/member/MemberServiceImpl.java
index 4f2f860e..d2239ac8 100644
--- a/src/main/java/com/example/spot/service/member/MemberServiceImpl.java
+++ b/src/main/java/com/example/spot/service/member/MemberServiceImpl.java
@@ -4,10 +4,7 @@
 import com.example.spot.api.exception.GeneralException;
 import com.example.spot.api.exception.handler.MemberHandler;
 import com.example.spot.domain.StudyReason;
-import com.example.spot.domain.enums.LoginType;
-import com.example.spot.domain.enums.Reason;
-import com.example.spot.domain.enums.Status;
-import com.example.spot.domain.enums.ThemeType;
+import com.example.spot.domain.enums.*;
 import com.example.spot.repository.StudyReasonRepository;
 import com.example.spot.security.utils.JwtTokenProvider;
 import com.example.spot.domain.Member;
@@ -29,6 +26,8 @@
 import com.example.spot.web.dto.member.kakao.KaKaoUser;
 import com.example.spot.web.dto.token.TokenResponseDTO.TokenDTO;
 import com.fasterxml.jackson.core.JsonProcessingException;
+import jakarta.persistence.EntityManager;
+import jakarta.persistence.PersistenceContext;
 import jakarta.servlet.http.HttpServletResponse;
 import java.io.IOException;
 import java.util.List;
@@ -63,6 +62,9 @@
 @RequiredArgsConstructor
 public class MemberServiceImpl implements MemberService {
 
+    @PersistenceContext
+    private EntityManager entityManager;
+
     // OAuth
     private final KaKaoOAuthService kaKaoOAuthService;
 
@@ -273,31 +275,54 @@ public SocialLoginSignInDTO signUpByKAKAOForTest(String code) throws JsonProcess
         // 응답에서 사용자 정보를 파싱
         KaKaoUser kaKaoUser = kaKaoOAuthService.getUserInfo(userInfoResponse);
 
-        if (memberRepository.existsByEmailAndLoginTypeNot(kaKaoUser.toMember().getEmail(), LoginType.KAKAO))
-            throw new GeneralException(ErrorStatus._MEMBER_EMAIL_EXIST);
+        // 다른 로그인 방식을 사용한 계정이 있는지 확인
+        if (memberRepository.existsByEmailAndLoginTypeNot(kaKaoUser.toMember().getEmail(), LoginType.KAKAO)) {
+            Member member = memberRepository.findByEmail(kaKaoUser.toMember().getEmail())
+                    .orElseThrow(() -> new MemberHandler(ErrorStatus._MEMBER_NOT_FOUND));
+
+            // 탈퇴한(inactive) 회원이면 기존 정보 삭제
+            if (member.getInactive() != null) {
+                refreshTokenRepository.deleteByMemberId(member.getId());
+                memberRepository.deleteById(member.getId());
+                entityManager.flush();
+            }
+            else {
+                throw new GeneralException(ErrorStatus._MEMBER_EMAIL_EXIST);
+            }
+        }
+
 
-        Boolean isSpotMember = false;
         // 사용자가 이미 존재하는지 확인
+        Boolean isSpotMember = false;
         if (memberRepository.existsByEmail(kaKaoUser.toMember().getEmail())) {
             // 존재하는 경우, 사용자 정보를 가져옴
             Member member = memberRepository.findByEmail(kaKaoUser.toMember().getEmail())
                 .orElseThrow(() -> new MemberHandler(ErrorStatus._MEMBER_NOT_FOUND));
-            isSpotMember = true;
-
-            // JWT 토큰 생성
-            TokenDTO token = jwtTokenProvider.createToken(member.getId());
-
-            saveRefreshToken(member, token);
-
-            // 로그인 DTO 반환
-            MemberSignInDTO memberSignInDto = MemberSignInDTO.builder()
-                    .tokens(token)
-                    .memberId(member.getId())
-                    .loginType(member.getLoginType())
-                    .email(member.getEmail())
-                    .build();
 
-            return SocialLoginSignInDTO.toDTO(isSpotMember, memberSignInDto);
+            // 탈퇴한(inactive) 회원이면 기존 정보 삭제
+            if (member.getInactive() != null) {
+                refreshTokenRepository.deleteByMemberId(member.getId());
+                memberRepository.deleteById(member.getId());
+                entityManager.flush();
+            }
+            else {
+                // JWT 토큰 생성
+                TokenDTO token = jwtTokenProvider.createToken(member.getId());
+
+                saveRefreshToken(member, token);
+
+                isSpotMember = true;
+
+                // 로그인 DTO 반환
+                MemberSignInDTO memberSignInDto = MemberSignInDTO.builder()
+                        .tokens(token)
+                        .memberId(member.getId())
+                        .loginType(member.getLoginType())
+                        .email(member.getEmail())
+                        .build();
+
+                return SocialLoginSignInDTO.toDTO(isSpotMember, memberSignInDto);
+            }
         }
 
         // 존재하지 않는 경우, 새로운 회원 정보 저장
@@ -587,17 +612,18 @@ public MemberTestDTO testMember(MemberInfoListDTO memberInfoListDTO) {
         // 회원 생성
         Member member = Member.builder()
                 .name(memberInfoListDTO.getName())
-                .carrier(memberInfoListDTO.getCarrier())
-                .birth(memberInfoListDTO.getBirth())
                 .nickname(memberInfoListDTO.getNickname())
+                .birth(memberInfoListDTO.getBirth())
+                .gender(Gender.UNKNOWN)
                 .email(memberInfoListDTO.getEmail())
-                .password(UUID.randomUUID().toString())
+                .carrier(memberInfoListDTO.getCarrier())
                 .phone(memberInfoListDTO.getPhone())
+                .password(UUID.randomUUID().toString())
+                .profileImage(memberInfoListDTO.getProfileImage())
                 .personalInfo(memberInfoListDTO.isPersonalInfo())
                 .idInfo(memberInfoListDTO.isIdInfo())
-                .profileImage(memberInfoListDTO.getProfileImage())
-                .status(Status.ON)
                 .loginType(LoginType.NORMAL)
+                .status(Status.ON)
                 .build();
 
         // 회원 저장
diff --git a/src/main/java/com/example/spot/service/memberstudy/MemberStudyCommandService.java b/src/main/java/com/example/spot/service/memberstudy/MemberStudyCommandService.java
index ac5607fb..28803106 100644
--- a/src/main/java/com/example/spot/service/memberstudy/MemberStudyCommandService.java
+++ b/src/main/java/com/example/spot/service/memberstudy/MemberStudyCommandService.java
@@ -14,8 +14,9 @@
 public interface MemberStudyCommandService {
 
     StudyWithdrawalResponseDTO.WithdrawalDTO withdrawFromStudy(Long studyId);
+    StudyWithdrawalResponseDTO.WithdrawalDTO withdrawHostFromStudy(Long studyId, StudyHostWithdrawRequestDTO requestDTO);
 
-    StudyTerminationResponseDTO.TerminationDTO terminateStudy(Long studyId);
+    StudyTerminationResponseDTO.TerminationDTO terminateStudy(Long studyId, String performance);
 
     // 스터디 신청 수락
     StudyApplyResponseDTO acceptAndRejectStudyApply(Long memberId, Long studyId, boolean isAccept);
diff --git a/src/main/java/com/example/spot/service/memberstudy/MemberStudyCommandServiceImpl.java b/src/main/java/com/example/spot/service/memberstudy/MemberStudyCommandServiceImpl.java
index 2a30badb..c70ee0d6 100644
--- a/src/main/java/com/example/spot/service/memberstudy/MemberStudyCommandServiceImpl.java
+++ b/src/main/java/com/example/spot/service/memberstudy/MemberStudyCommandServiceImpl.java
@@ -22,6 +22,7 @@
 import com.example.spot.web.dto.memberstudy.request.toDo.ToDoListResponseDTO.ToDoListCreateResponseDTO;
 import com.example.spot.web.dto.memberstudy.request.toDo.ToDoListResponseDTO.ToDoListUpdateResponseDTO;
 import com.example.spot.web.dto.memberstudy.response.*;
+import com.example.spot.web.dto.memberstudy.response.StudyWithdrawalResponseDTO.WithdrawalDTO;
 import com.example.spot.web.dto.study.response.StudyApplyResponseDTO;
 
 import java.time.LocalDate;
@@ -100,12 +101,39 @@ public StudyWithdrawalResponseDTO.WithdrawalDTO withdrawFromStudy(Long studyId)
         return StudyWithdrawalResponseDTO.WithdrawalDTO.toDTO(member, study);
     }
 
+    @Override
+    public WithdrawalDTO withdrawHostFromStudy(Long studyId, StudyHostWithdrawRequestDTO requestDTO) {
+        // Authorization
+        Long hostId = SecurityUtils.getCurrentUserId();
+        SecurityUtils.verifyUserId(hostId);
+
+        MemberStudy memberStudy = memberStudyRepository.findByMemberIdAndStudyIdAndStatus(hostId, studyId, ApplicationStatus.APPROVED)
+                .orElseThrow(() -> new StudyHandler(ErrorStatus._STUDY_MEMBER_NOT_FOUND));
+
+        if (!memberStudy.getIsOwned()) {
+            throw new StudyHandler(ErrorStatus._STUDY_OWNER_ONLY_CAN_WITHDRAW);
+        }
+
+        MemberStudy newHostStudy = memberStudyRepository.findByMemberIdAndStudyIdAndStatus(requestDTO.getNewHostId(), studyId, ApplicationStatus.APPROVED)
+                .orElseThrow(() -> new StudyHandler(ErrorStatus._STUDY_MEMBER_NOT_EXIST));
+
+        memberStudyRepository.delete(memberStudy);
+
+        newHostStudy.setIsOwned(true);
+        newHostStudy.setReason(requestDTO.getReason());
+
+        memberStudyRepository.save(newHostStudy);
+
+        return StudyWithdrawalResponseDTO.WithdrawalDTO.toDTO(newHostStudy.getMember(), newHostStudy.getStudy());
+    }
     /**
      * 운영중인 스터디를 종료하는 메서드입니다. 스터디장만 호출 가능합니다.
-     * @param studyId 종료할 스터디의 아이디를 입력 받습니다.
+     *
+     * @param studyId       종료할 스터디의 아이디를 입력 받습니다.
+     * @param performance   종료할 스터디의 성과를 입력 받습니다.
      * @return 종료된 스터디의 아이디, 이름, 상태를 반환합니다.
      */
-    public StudyTerminationResponseDTO.TerminationDTO terminateStudy(Long studyId) {
+    public StudyTerminationResponseDTO.TerminationDTO terminateStudy(Long studyId, String performance) {
 
         // Authorization
         Long memberId = SecurityUtils.getCurrentUserId();
@@ -126,7 +154,7 @@ public StudyTerminationResponseDTO.TerminationDTO terminateStudy(Long studyId) {
             throw new StudyHandler(ErrorStatus._STUDY_ALREADY_TERMINATED);
         }
 
-        study.setStatus(Status.OFF);
+        study.terminateStudy(performance);
         studyRepository.save(study);
 
         return StudyTerminationResponseDTO.TerminationDTO.toDTO(study);
diff --git a/src/main/java/com/example/spot/service/memberstudy/MemberStudyQueryService.java b/src/main/java/com/example/spot/service/memberstudy/MemberStudyQueryService.java
index 95c280b5..4cc90925 100644
--- a/src/main/java/com/example/spot/service/memberstudy/MemberStudyQueryService.java
+++ b/src/main/java/com/example/spot/service/memberstudy/MemberStudyQueryService.java
@@ -28,6 +28,9 @@ public interface MemberStudyQueryService {
     // 스터디 별 신청 회원 목록 조회하기
     StudyMemberResponseDTO findStudyApplicants(Long studyId);
 
+    // 스터디 호스트 조회하기
+    StudyMemberResDTO.StudyHostDTO getStudyHost(Long studyId);
+
     // 스터디 신청 정보 가져오기
     StudyMemberResponseDTO.StudyApplyMemberDTO findStudyApplication(Long studyId, Long memberId);
 
@@ -63,4 +66,5 @@ public interface MemberStudyQueryService {
 
     // 스터디 원 투두 리스트 조회
     ToDoListResponseDTO.ToDoListSearchResponseDTO getMemberToDoList(Long studyId, Long memberId, LocalDate date, PageRequest pageRequest);
+
 }
diff --git a/src/main/java/com/example/spot/service/memberstudy/MemberStudyQueryServiceImpl.java b/src/main/java/com/example/spot/service/memberstudy/MemberStudyQueryServiceImpl.java
index 2bc6cf44..735eed8f 100644
--- a/src/main/java/com/example/spot/service/memberstudy/MemberStudyQueryServiceImpl.java
+++ b/src/main/java/com/example/spot/service/memberstudy/MemberStudyQueryServiceImpl.java
@@ -1,6 +1,7 @@
 package com.example.spot.service.memberstudy;
 
 import com.example.spot.api.code.status.ErrorStatus;
+import com.example.spot.api.exception.handler.MemberHandler;
 import com.example.spot.api.exception.handler.StudyHandler;
 import com.example.spot.domain.Member;
 import com.example.spot.domain.Quiz;
@@ -178,6 +179,26 @@ public StudyMemberResponseDTO findStudyApplicants(Long studyId) {
         return new StudyMemberResponseDTO(memberDTOS);
     }
 
+    @Override
+    public StudyMemberResDTO.StudyHostDTO getStudyHost(Long studyId) {
+
+        // Authorization
+        Long memberId = SecurityUtils.getCurrentUserId();
+        Member member = memberRepository.findById(memberId)
+                .orElseThrow(() -> new MemberHandler(ErrorStatus._MEMBER_NOT_FOUND));
+
+        // 스터디 호스트 찾기
+        MemberStudy studyHost = memberStudyRepository.findByStudyIdAndIsOwned(studyId, true)
+                .orElseThrow(() -> new StudyHandler(ErrorStatus._STUDY_OWNER_NOT_FOUND));
+
+        // 로그인한 회원이 호스트인지 확인
+        if (studyHost.getMember().getId().equals(memberId)) {
+            return StudyMemberResDTO.StudyHostDTO.toDTO(true, member);
+        } else {
+            return StudyMemberResDTO.StudyHostDTO.toDTO(false, studyHost.getMember());
+        }
+    }
+
     /**
      * 스터디 신청자의 정보를 조회합니다.
      * @param studyId 스터디 ID
diff --git a/src/main/java/com/example/spot/web/controller/AdminController.java b/src/main/java/com/example/spot/web/controller/AdminController.java
index 32eabac5..cc455861 100644
--- a/src/main/java/com/example/spot/web/controller/AdminController.java
+++ b/src/main/java/com/example/spot/web/controller/AdminController.java
@@ -1,14 +1,18 @@
 package com.example.spot.web.controller;
 
+import com.example.spot.api.ApiResponse;
 import com.example.spot.api.code.status.ErrorStatus;
+import com.example.spot.api.code.status.SuccessStatus;
 import com.example.spot.api.exception.GeneralException;
+import com.example.spot.service.admin.AdminService;
+import com.example.spot.web.dto.admin.AdminResponseDTO;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.Parameter;
 import io.swagger.v3.oas.annotations.tags.Tag;
+import lombok.RequiredArgsConstructor;
 import org.springframework.web.bind.annotation.DeleteMapping;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.PathVariable;
-import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestHeader;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestParam;
@@ -17,8 +21,31 @@
 @Tag(name = "관리자 - 개발 중", description = "관리자 관련 API")
 @RestController
 @RequestMapping("/spot/admin")
+@RequiredArgsConstructor
 public class AdminController {
 
+    private final AdminService adminService;
+
+/* ----------------------------- 회원 정보 관리 API ------------------------------------- */
+
+    @Operation(summary = "[회원 정보 관리] 탈퇴 회원 영구 삭제 수동 실행 API",
+            description = """
+            ## [회원 정보 관리] inactive 시점 이후로 30일이 지난 회원의 정보를 DB에서 영구적으로 삭제합니다.
+            * <탈퇴 회원 영구 삭제>는 스케줄러에 의해 오전 6시마다 실행되고 있습니다.
+            * 오류로 인하여 수동 삭제가 필요한 경우 해당 API를 호출해주시기 바랍니다.
+            """)
+    @DeleteMapping("/members/removal")
+    public ApiResponse<AdminResponseDTO.DeletedMemberListDTO> deleteInactiveMembers() {
+        // 관리자 인증
+        if (!adminService.getIsAdmin()) {
+            throw new GeneralException(ErrorStatus._NOT_ADMIN);
+        }
+        AdminResponseDTO.DeletedMemberListDTO deletedMemberListDTO = adminService.deleteInactiveMembers();
+        return ApiResponse.onSuccess(SuccessStatus._MEMBER_DELETED, deletedMemberListDTO);
+    }
+
+/* ----------------------------- 신고 내역 관리 API ------------------------------------- */
+
     @Operation(
         summary = "[신고 내역 조회 - 개발중] 특정 스터디 신고 내역 조회",
         description = """
diff --git a/src/main/java/com/example/spot/web/controller/AuthController.java b/src/main/java/com/example/spot/web/controller/AuthController.java
index ef894d96..45ea453c 100644
--- a/src/main/java/com/example/spot/web/controller/AuthController.java
+++ b/src/main/java/com/example/spot/web/controller/AuthController.java
@@ -65,6 +65,22 @@ public ApiResponse<MemberResponseDTO.MemberInfoCreationDTO> signUpAndPartialUpda
         return ApiResponse.onSuccess(SuccessStatus._MEMBER_UPDATED, memberInfoCreationDTO);
     }
 
+    @Tag(name = "회원 관리 API - 개발 완료", description = "회원 관리 API")
+    @Operation(summary = "[공통 회원 관리] 회원탈퇴 API",
+            description = """
+            ## [공통 회원 관리] 로그인한 회원이 SPOT을 탈퇴할 때 사용되는 API입니다.
+            * Authorization 헤더에 액세스 토큰을 포함해야 합니다.
+            * 회원탈퇴 시 해당 회원의 inactive(LocalDateTime) 필드가 활성화 됩니다.
+            * 회원 정보 및 회원의 스터디 정보는 30일간 DB에 저장되며 30일이 지나면 자동으로 삭제됩니다.
+            * 30일 이후 정보 삭제 시 "로그인 이메일", "성명", "생년월일 정보", "진행중 스터디", \
+            "모집중 스터디", "스터디 찜 정보", "게시글", "댓글", "사진", "관심사", "관심지역"이  삭제됩니다.
+            """)
+    @PatchMapping("/withdraw")
+    public ApiResponse<MemberResponseDTO.InactiveMemberDTO> withdraw() {
+        MemberResponseDTO.InactiveMemberDTO inactiveMemberDTO = authService.withdraw();
+        return ApiResponse.onSuccess(SuccessStatus._MEMBER_DELETED, inactiveMemberDTO);
+    }
+
 /* ----------------------------- 네이버 소셜로그인 API ------------------------------------- */
 
     @Tag(name = "테스트 용 API", description = "테스트 용 API")
@@ -259,7 +275,7 @@ public ApiResponse<MemberResponseDTO.MemberSignInDTO> login(
         description = """
             ## [로그아웃] 로그아웃 API입니다.
             로그아웃을 진행합니다.
-            로그아웃 시, 사용 하던 액세스 토큰과 리프레시 토큰은 더 이상 사용이 불가능합니다. 
+            로그아웃 시, 사용 하던 액세스 토큰과 리프레시 토큰은 더 이상 사용이 불가능합니다.
             다시 서비스를 이용하기 위해서는 로그인을 다시 진행해야 합니다.
             """)
     @PostMapping("/logout")
diff --git a/src/main/java/com/example/spot/web/controller/MemberController.java b/src/main/java/com/example/spot/web/controller/MemberController.java
index 092b26a1..c6082ff8 100644
--- a/src/main/java/com/example/spot/web/controller/MemberController.java
+++ b/src/main/java/com/example/spot/web/controller/MemberController.java
@@ -67,7 +67,7 @@ public ApiResponse<MemberResponseDTO.MemberTestDTO> testMember(
             ## [회원 권한 부여] 해당하는 회원에게 관리자 권한을 부여합니다.
             테스트를 위해 구현한 테스트 용 API입니다.
             회원의 ID를 입력 받아 관리자 권한을 부여합니다.
-            성공 여부와 회원 ID가 반환 됩니다. 
+            성공 여부와 회원 ID가 반환 됩니다.
              """)
     @PostMapping("/members/test/admin")
     public ApiResponse<MemberResponseDTO.MemberUpdateDTO> toAdmin(){
diff --git a/src/main/java/com/example/spot/web/controller/MemberStudyController.java b/src/main/java/com/example/spot/web/controller/MemberStudyController.java
index e41ef971..65d3f740 100644
--- a/src/main/java/com/example/spot/web/controller/MemberStudyController.java
+++ b/src/main/java/com/example/spot/web/controller/MemberStudyController.java
@@ -16,6 +16,7 @@
 import com.example.spot.web.dto.memberstudy.request.toDo.ToDoListResponseDTO.ToDoListUpdateResponseDTO;
 import com.example.spot.web.dto.memberstudy.response.*;
 import com.example.spot.web.dto.study.response.*;
+import com.example.spot.web.dto.study.response.StudyMemberResponseDTO;
 import com.example.spot.web.dto.study.response.StudyMemberResponseDTO.StudyApplicantDTO;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.Parameter;
@@ -54,14 +55,35 @@ public ApiResponse<StudyWithdrawalResponseDTO.WithdrawalDTO> withdrawFromStudy(@
         return ApiResponse.onSuccess(SuccessStatus._STUDY_MEMBER_DELETED, withdrawalDTO);
     }
 
+    @Tag(name = "진행중인 스터디")
+    @Operation(summary = "[진행중인 스터디] 스터디 호스트 탈퇴",
+            description = """
+               ## [진행중인 스터디] 특정 스터디의 호스트가 해당 스터디에서 탈퇴합니다.
+               탈퇴 시, 호스트 권한이 회수되며 스터디에서 제외됩니다. 
+               요청 시, 새로운 호스트의 아이디와 임명 사유를 입력해야 합니다.
+           """)
+    @DeleteMapping("/studies/{studyId}/hosts/withdrawal")
+    public ApiResponse<StudyWithdrawalResponseDTO.WithdrawalDTO> withdrawHostFromStudy(
+            @PathVariable Long studyId,
+            @RequestBody StudyHostWithdrawRequestDTO requestDTO) {
+        StudyWithdrawalResponseDTO.WithdrawalDTO withdrawalDTO =
+                memberStudyCommandService.withdrawHostFromStudy(studyId, requestDTO);
+        return ApiResponse.onSuccess(SuccessStatus._STUDY_MEMBER_DELETED, withdrawalDTO);
+    }
+
+
     @Tag(name = "진행중인 스터디")
     @Operation(summary = "[진행중인 스터디] 스터디 끝내기", description = """ 
         ## [진행중인 스터디] 마이페이지 > 진행중 > 진행중인 스터디의 메뉴 클릭, 로그인한 회원이 운영중인 스터디를 끝냅니다.
-        로그인한 회원이 운영하는 특정 스터디에 대해 study status OFF로 전환합니다.
+        * 로그인한 회원이 운영하는 특정 스터디에 대해 study status OFF로 전환합니다.
+        * 스터디 성과를 입력받아 DB에 저장합니다.
         """)
     @PatchMapping("/studies/{studyId}/termination")
-    public ApiResponse<StudyTerminationResponseDTO.TerminationDTO> terminateStudy(@PathVariable Long studyId) {
-        StudyTerminationResponseDTO.TerminationDTO terminationDTO = memberStudyCommandService.terminateStudy(studyId);
+    public ApiResponse<StudyTerminationResponseDTO.TerminationDTO> terminateStudy(
+            @PathVariable @ExistStudy Long studyId,
+            @RequestParam @TextLength(min=1, max=30) String performance
+    ) {
+        StudyTerminationResponseDTO.TerminationDTO terminationDTO = memberStudyCommandService.terminateStudy(studyId, performance);
         return ApiResponse.onSuccess(SuccessStatus._STUDY_TERMINATED, terminationDTO);
     }
 
@@ -157,6 +179,7 @@ public ApiResponse<StudyApplyResponseDTO> rejectApplicantForTest(
 
 
 /* ----------------------------- 스터디 상세 정보 관련 API ------------------------------------- */
+
     @Tag(name = "스터디 상세 정보")
     @Operation(summary = "[스터디 상세 정보] 스터디 최근 공지 1개 불러오기", description = """ 
         ## [스터디 상세 정보] 내 스터디 > 스터디 클릭, 로그인한 회원이 참여하는 특정 스터디의 최근 공지 1개를 불러옵니다.
@@ -192,6 +215,20 @@ public ApiResponse<StudyMemberResponseDTO> getStudyMembers(
         return ApiResponse.onSuccess(SuccessStatus._STUDY_MEMBER_FOUND, studyMemberResponseDTO);
     }
 
+    @Tag(name = "스터디 상세 정보")
+    @Operation(summary = "[스터디 상세 정보] 스터디 호스트 정보 불러오기", description = """ 
+        ## [스터디 상세 정보] 로그인한 회원이 참여하는 특정 스터디의 호스트 정보를 조회합니다.
+        * isOwned : 로그인한 회원이 호스트인지 true or false로 반환
+        * host : 호스트의 id와 nickname 반환
+        """)
+    @GetMapping("/studies/{studyId}/host")
+    public ApiResponse<StudyMemberResDTO.StudyHostDTO> getStudyHost(
+            @PathVariable @ExistStudy Long studyId)
+    {
+        StudyMemberResDTO.StudyHostDTO studyHostDTO = memberStudyQueryService.getStudyHost(studyId);
+        return ApiResponse.onSuccess(SuccessStatus._STUDY_HOST_FOUND, studyHostDTO);
+    }
+
 
 /* ----------------------------- 스터디 일정 관련 API ------------------------------------- */
 
diff --git a/src/main/java/com/example/spot/web/dto/admin/AdminResponseDTO.java b/src/main/java/com/example/spot/web/dto/admin/AdminResponseDTO.java
new file mode 100644
index 00000000..d1e5deb1
--- /dev/null
+++ b/src/main/java/com/example/spot/web/dto/admin/AdminResponseDTO.java
@@ -0,0 +1,47 @@
+package com.example.spot.web.dto.admin;
+
+import com.example.spot.domain.Member;
+import lombok.AccessLevel;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+
+import java.time.LocalDateTime;
+import java.util.List;
+
+@Getter
+public class AdminResponseDTO {
+
+    @Getter
+    @RequiredArgsConstructor(access = AccessLevel.PRIVATE)
+    @Builder(access = AccessLevel.PRIVATE)
+    public static class DeletedMemberListDTO {
+        private final LocalDateTime deletedAt;
+        private final List<DeletedMemberDTO> deletedMembers;
+
+        public static DeletedMemberListDTO toDTO(List<Member> members) {
+            return DeletedMemberListDTO.builder()
+                    .deletedAt(LocalDateTime.now())
+                    .deletedMembers(members.stream()
+                            .map(DeletedMemberDTO::toDTO)
+                            .toList())
+                    .build();
+        }
+    }
+
+    @Getter
+    @RequiredArgsConstructor(access = AccessLevel.PRIVATE)
+    @Builder(access = AccessLevel.PRIVATE)
+    public static class DeletedMemberDTO {
+
+        private final Long memberId;
+        private final String email;
+
+        public static DeletedMemberDTO toDTO(Member member) {
+            return DeletedMemberDTO.builder()
+                    .memberId(member.getId())
+                    .email(member.getEmail())
+                    .build();
+        }
+    }
+}
diff --git a/src/main/java/com/example/spot/web/dto/member/MemberResponseDTO.java b/src/main/java/com/example/spot/web/dto/member/MemberResponseDTO.java
index 2048de1e..0aa7bc02 100644
--- a/src/main/java/com/example/spot/web/dto/member/MemberResponseDTO.java
+++ b/src/main/java/com/example/spot/web/dto/member/MemberResponseDTO.java
@@ -183,5 +183,26 @@ public static ReportedMemberDTO toDTO(Member member) {
                     .build();
         }
     }
+
+    @Getter
+    @RequiredArgsConstructor(access = AccessLevel.PRIVATE)
+    @Builder(access = AccessLevel.PRIVATE)
+    public static class InactiveMemberDTO {
+
+        private final Long memberId;
+        private final String name;
+        private final String email;
+        private final LocalDateTime inactive;
+
+        public static InactiveMemberDTO toDTO(Member member) {
+            return InactiveMemberDTO.builder()
+                    .memberId(member.getId())
+                    .name(member.getName())
+                    .email(member.getEmail())
+                    .inactive(member.getInactive())
+                    .build();
+        }
+    }
+
 }
 
diff --git a/src/main/java/com/example/spot/web/dto/memberstudy/request/StudyHostWithdrawRequestDTO.java b/src/main/java/com/example/spot/web/dto/memberstudy/request/StudyHostWithdrawRequestDTO.java
new file mode 100644
index 00000000..cadb03ae
--- /dev/null
+++ b/src/main/java/com/example/spot/web/dto/memberstudy/request/StudyHostWithdrawRequestDTO.java
@@ -0,0 +1,16 @@
+package com.example.spot.web.dto.memberstudy.request;
+
+
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@Getter
+@NoArgsConstructor
+@AllArgsConstructor
+public class StudyHostWithdrawRequestDTO {
+
+    private Long newHostId;
+    private String reason;
+
+}
diff --git a/src/main/java/com/example/spot/web/dto/memberstudy/response/StudyMemberResDTO.java b/src/main/java/com/example/spot/web/dto/memberstudy/response/StudyMemberResDTO.java
new file mode 100644
index 00000000..10cdcd9f
--- /dev/null
+++ b/src/main/java/com/example/spot/web/dto/memberstudy/response/StudyMemberResDTO.java
@@ -0,0 +1,39 @@
+package com.example.spot.web.dto.memberstudy.response;
+
+import com.example.spot.domain.Member;
+import lombok.AccessLevel;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+
+@Getter
+public class StudyMemberResDTO {
+
+    @Getter
+    @RequiredArgsConstructor(access = AccessLevel.PRIVATE)
+    @Builder(access = AccessLevel.PRIVATE)
+    public static class StudyHostDTO {
+        private final Boolean isOwned;
+        private final HostInfoDTO host;
+        public static StudyHostDTO toDTO(Boolean isOwned, Member host) {
+            return StudyHostDTO.builder()
+                    .isOwned(isOwned)
+                    .host(HostInfoDTO.toDTO(host))
+                    .build();
+        }
+    }
+
+    @Getter
+    @RequiredArgsConstructor(access = AccessLevel.PRIVATE)
+    @Builder(access = AccessLevel.PRIVATE)
+    private static class HostInfoDTO {
+        private final Long memberId;
+        private final String nickname;
+        public static HostInfoDTO toDTO(Member host) {
+            return HostInfoDTO.builder()
+                    .memberId(host.getId())
+                    .nickname(host.getNickname())
+                    .build();
+        }
+    }
+}
diff --git a/src/test/java/com/example/spot/service/memberstudy/MemberStudyCommandServiceTest.java b/src/test/java/com/example/spot/service/memberstudy/MemberStudyCommandServiceTest.java
index 1e7bdc42..859b6b8f 100644
--- a/src/test/java/com/example/spot/service/memberstudy/MemberStudyCommandServiceTest.java
+++ b/src/test/java/com/example/spot/service/memberstudy/MemberStudyCommandServiceTest.java
@@ -27,12 +27,10 @@
 
 import com.example.spot.web.dto.memberstudy.response.StudyTerminationResponseDTO;
 import com.example.spot.web.dto.memberstudy.response.StudyWithdrawalResponseDTO;
-import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.DisplayName;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
-import org.mockito.BDDMockito;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
@@ -218,7 +216,7 @@ void terminateStudy_Success() {
                 .thenReturn(Optional.of(memberStudy));
 
         // when
-        StudyTerminationResponseDTO.TerminationDTO result = memberStudyCommandService.terminateStudy(1L);
+        StudyTerminationResponseDTO.TerminationDTO result = memberStudyCommandService.terminateStudy(1L, "스터디 성과");
 
         // then
         assertNotNull(result);
@@ -254,7 +252,7 @@ void terminateStudy_NotStudyOwner_Fail() {
                 .thenReturn(Optional.of(memberStudy));
 
         // when & then
-        assertThrows(StudyHandler.class, () -> memberStudyCommandService.terminateStudy(1L));
+        assertThrows(StudyHandler.class, () -> memberStudyCommandService.terminateStudy(1L, "스터디 성과"));
     }
 
     @Test
@@ -284,7 +282,7 @@ void terminateStudy_AlreadyTerminated_Fail() {
                 .thenReturn(Optional.of(memberStudy));
 
         // when & then
-        assertThrows(StudyHandler.class, () -> memberStudyCommandService.terminateStudy(1L));
+        assertThrows(StudyHandler.class, () -> memberStudyCommandService.terminateStudy(1L, "스터디 성과"));
     }