diff --git a/src/main/java/com/haru/api/domain/meeting/service/MeetingCommandServiceImpl.java b/src/main/java/com/haru/api/domain/meeting/service/MeetingCommandServiceImpl.java
index 8e6a8730..afb1528c 100644
--- a/src/main/java/com/haru/api/domain/meeting/service/MeetingCommandServiceImpl.java
+++ b/src/main/java/com/haru/api/domain/meeting/service/MeetingCommandServiceImpl.java
@@ -139,7 +139,8 @@ public void updateMeetingTitle(User user, Meeting meeting, MeetingRequestDTO.upd
 
         meeting.updateTitle(request.getTitle());
 
-        markdownFileUploader.updateFileTitle(meeting.getProceedingPdfKeyName(), request.getTitle());
+        markdownFileUploader.updateFileTitle(meeting.getProceedingPdfKeyName(), request.getTitle() + ".pdf");
+        markdownFileUploader.updateFileTitle(meeting.getProceedingWordKeyName(), request.getTitle() + ".docx");
 
         meetingRepository.save(meeting);
     }
diff --git a/src/main/java/com/haru/api/infra/s3/AmazonS3Manager.java b/src/main/java/com/haru/api/infra/s3/AmazonS3Manager.java
index ae161a07..0f4fe1b8 100644
--- a/src/main/java/com/haru/api/infra/s3/AmazonS3Manager.java
+++ b/src/main/java/com/haru/api/infra/s3/AmazonS3Manager.java
@@ -153,6 +153,7 @@ public byte[] downloadFile(String keyName) {
         }
     }
 
+    // newDisplayName에 확장자 포함되어있음
     public void updateFileTitle(String keyName, String newDisplayName) {
 
         try {
diff --git a/src/main/java/com/haru/api/infra/s3/MarkdownFileUploader.java b/src/main/java/com/haru/api/infra/s3/MarkdownFileUploader.java
index 6c7e88d3..41900bc1 100644
--- a/src/main/java/com/haru/api/infra/s3/MarkdownFileUploader.java
+++ b/src/main/java/com/haru/api/infra/s3/MarkdownFileUploader.java
@@ -42,7 +42,7 @@ public String createOrUpdatePdf(String markdownText, String featurePath, String
         }
 
         // 3. 결정된 키로 PDF 파일을 S3에 업로드
-        amazonS3Manager.uploadFileWithTitle(pdfKeyToUse, pdfBytes, "application/pdf", fileTitle);
+        amazonS3Manager.uploadFileWithTitle(pdfKeyToUse, pdfBytes, "application/pdf", fileTitle + ".pdf");
         log.info("PDF 업로드/갱신 성공. Key: {}", pdfKeyToUse);
 
         // 4. 사용된 PDF의 key를 반환
@@ -65,7 +65,7 @@ public String createOrUpdateWord(String markdownText, String featurePath, String
 
         // 3. 결정된 키로 Word 파일을 S3에 업로드
         String contentType = "application/vnd.openxmlformats-officedocument.wordprocessingml.document";
-        amazonS3Manager.uploadFileWithTitle(wordKeyToUse, wordBytes, contentType, fileTitle);
+        amazonS3Manager.uploadFileWithTitle(wordKeyToUse, wordBytes, contentType, fileTitle + ".docx");
         log.info("Word 파일 업로드/갱신 성공. Key: {}", wordKeyToUse);
 
         // 4. 사용된 Word의 key를 반환