diff --git a/src/test/java/com/example/schoolproject/controller/TaskControllerTest.java b/src/test/java/com/example/schoolproject/controller/TaskControllerTest.java
new file mode 100644
index 0000000..fddbe7b
--- /dev/null
+++ b/src/test/java/com/example/schoolproject/controller/TaskControllerTest.java
@@ -0,0 +1,104 @@
+package com.example.schoolproject.controller;
+
+import com.example.schoolproject.dto.TaskDTO;
+import com.example.schoolproject.entity.Task;
+import com.example.schoolproject.entity.TaskStatus;
+import com.example.schoolproject.integration.PostgresContainer;
+import com.example.schoolproject.repository.TaskRepository;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.http.MediaType;
+import org.springframework.test.web.servlet.MockMvc;
+
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.*;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.*;
+
+@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
+@AutoConfigureMockMvc
+public class TaskControllerTest extends PostgresContainer {
+
+    @SuppressWarnings("SpringJavaInjectionPointsAutowiringInspection")
+    @Autowired
+    private MockMvc mockMvc;
+
+    @SuppressWarnings("SpringJavaInjectionPointsAutowiringInspection")
+    @Autowired
+    private ObjectMapper objectMapper;
+
+    @Autowired
+    private TaskRepository repository;
+
+    private Long savedTaskId;
+
+    @BeforeEach
+    void setUp() {
+        repository.deleteAll();
+        Task saved = repository.save(getTask());
+        savedTaskId = saved.getId();
+    }
+
+    private Task getTask() {
+        return new Task(null, "title", "description", 10L, TaskStatus.TODO);
+    }
+
+    private TaskDTO getTaskDTO() {
+        return new TaskDTO("title", "description", 10L, TaskStatus.TODO);
+    }
+
+    @Test
+    void shouldReturnAllTasks() throws Exception {
+        mockMvc.perform(get("/tasks"))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$[0].title").value("title"))
+                .andExpect(jsonPath("$[0].description").value("description"))
+                .andExpect(jsonPath("$[0].userId").value(10L));
+    }
+
+    @Test
+    void shouldReturnTaskById() throws Exception {
+        mockMvc.perform(get("/tasks/" + savedTaskId))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$.title").value("title"))
+                .andExpect(jsonPath("$.description").value("description"))
+                .andExpect(jsonPath("$.userId").value(10L));
+    }
+
+    @Test
+    void shouldCreateTask() throws Exception {
+        mockMvc.perform(post("/tasks")
+                .contentType(MediaType.APPLICATION_JSON)
+                .content(objectMapper.writeValueAsString(getTaskDTO())))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$.title").value("title"))
+                .andExpect(jsonPath("$.description").value("description"))
+                .andExpect(jsonPath("$.userId").value(10L));
+    }
+
+    @Test
+    void shouldUpdateTask() throws Exception {
+        mockMvc.perform(put("/tasks/" + savedTaskId)
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content(objectMapper.writeValueAsString(getTaskDTO())))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$.title").value("title"))
+                .andExpect(jsonPath("$.description").value("description"))
+                .andExpect(jsonPath("$.userId").value(10L));
+    }
+
+    @Test
+    void shouldDeleteTask() throws Exception {
+        mockMvc.perform(delete("/tasks/" + savedTaskId))
+                .andExpect(status().isNoContent());
+    }
+
+    @Test
+    void shouldReturnNotFoundWhenTaskDoesNotExist() throws Exception {
+        mockMvc.perform(get("/tasks/99999"))
+                .andExpect(status().isNotFound())
+                .andExpect(content().string("Task with id 99999 is not found"));
+    }
+}
diff --git a/src/test/java/com/example/schoolproject/integration/PostgresContainer.java b/src/test/java/com/example/schoolproject/integration/PostgresContainer.java
new file mode 100644
index 0000000..8b38a1f
--- /dev/null
+++ b/src/test/java/com/example/schoolproject/integration/PostgresContainer.java
@@ -0,0 +1,21 @@
+package com.example.schoolproject.integration;
+
+import org.springframework.test.context.DynamicPropertyRegistry;
+import org.springframework.test.context.DynamicPropertySource;
+import org.testcontainers.containers.PostgreSQLContainer;
+import org.testcontainers.junit.jupiter.Container;
+import org.testcontainers.junit.jupiter.Testcontainers;
+
+@Testcontainers
+public class PostgresContainer {
+
+    @Container
+    public static PostgreSQLContainer<?> postgres = new PostgreSQLContainer<>("postgres:16");
+
+    @DynamicPropertySource
+    public static void properties(DynamicPropertyRegistry registry) {
+        registry.add("spring.datasource.url", postgres::getJdbcUrl);
+        registry.add("spring.datasource.username", postgres::getUsername);
+        registry.add("spring.datasource.password", postgres::getPassword);
+    }
+}
diff --git a/src/test/java/com/example/schoolproject/mapper/MainMapperTest.java b/src/test/java/com/example/schoolproject/mapper/MainMapperTest.java
new file mode 100644
index 0000000..a77e219
--- /dev/null
+++ b/src/test/java/com/example/schoolproject/mapper/MainMapperTest.java
@@ -0,0 +1,47 @@
+package com.example.schoolproject.mapper;
+
+import com.example.schoolproject.dto.TaskDTO;
+import com.example.schoolproject.dto.TaskStatusUpdateDTO;
+import com.example.schoolproject.entity.Task;
+import com.example.schoolproject.entity.TaskStatus;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mapstruct.factory.Mappers;
+import org.mockito.junit.jupiter.MockitoExtension;
+
+@ExtendWith(MockitoExtension.class)
+public class MainMapperTest {
+
+    private MainMapper mapper = Mappers.getMapper(MainMapper.class);
+
+    private Task getCreatedTask() {
+        return new Task(1L, "title", "description", 10L, TaskStatus.TODO);
+    }
+
+    private TaskDTO getCreatedTaskDTO() {
+        return new TaskDTO("title", "description", 10L, TaskStatus.TODO);
+    }
+
+    private TaskStatusUpdateDTO getTaskStatusUpdateDTO() {
+        return new TaskStatusUpdateDTO(1L, TaskStatus.TODO);
+    }
+
+    @Test
+    void shouldReturnTaskDTO() {
+        TaskDTO result = mapper.toDTO(getCreatedTask());
+        Assertions.assertEquals(result, getCreatedTaskDTO());
+    }
+
+    @Test
+    void shouldReturnTaskEntity() {
+        Task result = mapper.toEntity(getCreatedTaskDTO());
+        Assertions.assertEquals(result, getCreatedTask());
+    }
+
+    @Test
+    void shouldReturnTaskStatusUpdateDTO() {
+        TaskStatusUpdateDTO result = mapper.toStatusUpdateDTO(getCreatedTask());
+        Assertions.assertEquals(result, getTaskStatusUpdateDTO());
+    }
+}
diff --git a/src/test/java/com/example/schoolproject/service/TaskServiceTest.java b/src/test/java/com/example/schoolproject/service/TaskServiceTest.java
new file mode 100644
index 0000000..9d46905
--- /dev/null
+++ b/src/test/java/com/example/schoolproject/service/TaskServiceTest.java
@@ -0,0 +1,162 @@
+package com.example.schoolproject.service;
+
+import com.example.schoolproject.dto.TaskDTO;
+import com.example.schoolproject.dto.TaskStatusUpdateDTO;
+import com.example.schoolproject.entity.Task;
+import com.example.schoolproject.entity.TaskStatus;
+import com.example.schoolproject.exception.TaskNotFoundException;
+import com.example.schoolproject.kafka.KafkaTaskProducer;
+import com.example.schoolproject.mapper.MainMapper;
+import com.example.schoolproject.repository.TaskRepository;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+
+import java.util.Collections;
+import java.util.List;
+import java.util.Optional;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.mockito.Mockito.*;
+
+@ExtendWith(MockitoExtension.class)
+public class TaskServiceTest {
+
+    @Mock
+    private TaskRepository taskRepository;
+
+    @Mock
+    private KafkaTaskProducer kafkaTaskProducer;
+
+    @Mock
+    private MainMapper mapper;
+
+    private static final Long ID = 1L;
+    private static final String TASKS_NOT_FOUND = "Tasks are not found";
+    private static final String TASK_NOT_FOUND = "Task with id " + ID + " is not found";
+
+    @BeforeEach
+    void setUp() {
+    }
+
+    private Task getCreatedTask() {
+        return new Task(ID, "title", "description", 10L, TaskStatus.TODO);
+    }
+
+    private TaskDTO getCreatedTaskDTO() {
+        return new TaskDTO("title", "description", 10L, TaskStatus.TODO);
+    }
+
+    private Task getUpdatedTask() {
+        return new Task(ID, "newTitle", "newDescription", 11L, TaskStatus.DONE);
+    }
+
+    private TaskDTO getUpdatedTaskDTO() {
+        return new TaskDTO("newTitle", "newDescription", 11L, TaskStatus.DONE);
+    }
+
+    private TaskStatusUpdateDTO getTaskStatusUpdateDTO() {
+        return new TaskStatusUpdateDTO(ID, TaskStatus.DONE);
+    }
+
+    private TaskService getTaskService() {
+        return new TaskServiceImpl(taskRepository, mapper, kafkaTaskProducer);
+    }
+
+    @Test
+    void shouldReturnTaskByIdWhenExist() {
+        Task task = getCreatedTask();
+        TaskDTO taskDTO = getCreatedTaskDTO();
+        TaskService service = getTaskService();
+        when(taskRepository.findById(ID)).thenReturn(Optional.of(task));
+        when(mapper.toDTO(task)).thenReturn(taskDTO);
+        TaskDTO result = service.getTaskById(ID);
+        Assertions.assertNotNull(result);
+        assertEquals(taskDTO, result);
+        verify(taskRepository, times(1)).findById(ID);
+    }
+
+    @Test
+    void shouldTrowExceptionWhenTaskNotFoundById() {
+        TaskService service = getTaskService();
+        when(taskRepository.findById(ID)).thenReturn(Optional.empty());
+        TaskNotFoundException exception = Assertions.assertThrows(TaskNotFoundException.class, () -> service.getTaskById(ID));
+        verify(taskRepository).findById(any());
+        assertEquals(TASK_NOT_FOUND, exception.getMessage());
+    }
+
+    @Test
+    void shouldReturnAllTasksWhenExist() {
+        Task task = getCreatedTask();
+        TaskDTO taskDTO = getCreatedTaskDTO();
+        TaskService service = getTaskService();
+        when(taskRepository.findAll()).thenReturn(List.of(task));
+        when(mapper.toDTO(task)).thenReturn(taskDTO);
+        List<TaskDTO> result = service.getAllTasks();
+        Assertions.assertNotNull(result);
+        assertEquals(1, result.size());
+        assertEquals(taskDTO, result.get(0));
+        verify(taskRepository, times(1)).findAll();
+    }
+
+    @Test
+    void shouldThrowExceptionWhenTasksNotFound() {
+        TaskService service = getTaskService();
+        when(taskRepository.findAll()).thenReturn(Collections.emptyList());
+        TaskNotFoundException exception = Assertions.assertThrows(TaskNotFoundException.class, () -> service.getAllTasks());
+        verify(taskRepository).findAll();
+        assertEquals(TASKS_NOT_FOUND, exception.getMessage());
+    }
+
+    @Test
+    void shouldDeleteTaskWhenExist() {
+        TaskService service = getTaskService();
+        when(taskRepository.existsById(ID)).thenReturn(true);
+        service.deleteTask(ID);
+        verify(taskRepository, times(1)).existsById(ID);
+        verify(taskRepository, times(1)).deleteById(ID);
+    }
+
+    @Test
+    void shouldThrowExceptionInsteadDeleting() {
+        TaskService service = getTaskService();
+        when(taskRepository.existsById(ID)).thenReturn(false);
+        TaskNotFoundException exception = Assertions.assertThrows(TaskNotFoundException.class, () -> service.deleteTask(ID));
+        verify(taskRepository).existsById(ID);
+        verify(taskRepository, never()).deleteById(any());
+        assertEquals(TASK_NOT_FOUND, exception.getMessage());
+    }
+
+    @Test
+    void shouldCreateTask() {
+        Task task = getCreatedTask();
+        TaskDTO taskDTO = getCreatedTaskDTO();
+        TaskService service = getTaskService();
+        when(mapper.toEntity(taskDTO)).thenReturn(task);
+        when(taskRepository.save(task)).thenReturn(task);
+        when(mapper.toDTO(task)).thenReturn(taskDTO);
+        TaskDTO result = service.createTask(taskDTO);
+        assertEquals(taskDTO, result);
+        verify(taskRepository, times(1)).save(task);
+    }
+
+    @Test
+    void shouldUpdateTask() {
+        Task task = getCreatedTask();
+        TaskService service = getTaskService();
+        Task updatedTask = getUpdatedTask();
+        TaskDTO updatedTaskDTO = getUpdatedTaskDTO();
+        TaskStatusUpdateDTO taskStatusUpdateDTO = getTaskStatusUpdateDTO();
+        when(taskRepository.findById(ID)).thenReturn(Optional.of(task));
+        when(taskRepository.save(any(Task.class))).thenReturn(updatedTask);
+        when(mapper.toDTO(updatedTask)).thenReturn(updatedTaskDTO);
+        when(mapper.toStatusUpdateDTO(updatedTask)).thenReturn(taskStatusUpdateDTO);
+        TaskDTO result = service.updateTask(task.getId(), updatedTaskDTO);
+        assertEquals(updatedTaskDTO, result);
+        verify(taskRepository, times(1)).save(updatedTask);
+        verify(kafkaTaskProducer).sendTo(any(), eq(taskStatusUpdateDTO));
+    }
+}