diff --git a/src/main/java/com/trendithon/timetris/domain/mainpage/domain/Category.java b/src/main/java/com/trendithon/timetris/domain/mainpage/domain/Category.java
index 57d45ad..765ef7d 100644
--- a/src/main/java/com/trendithon/timetris/domain/mainpage/domain/Category.java
+++ b/src/main/java/com/trendithon/timetris/domain/mainpage/domain/Category.java
@@ -8,6 +8,9 @@
 import lombok.Getter;
 import lombok.NoArgsConstructor;
 
+import java.util.ArrayList;
+import java.util.List;
+
 @Entity
 @Getter
 @AllArgsConstructor
@@ -18,10 +21,18 @@ public class Category {
     private long id;
     private String name;
     private String colorCode;
+
     @ManyToOne(fetch = FetchType.LAZY)
     @JoinColumn(name = "userId")
     private User user;
 
+    @OneToMany(mappedBy = "category", cascade = CascadeType.ALL, orphanRemoval = true)
+    private List<Do> doList = new ArrayList<>();
+
+    @OneToMany(mappedBy = "category", cascade = CascadeType.ALL, orphanRemoval = true)
+    private List<Plan> planList = new ArrayList<>();
+
+
     public Category(CategoryCreateDTO categoryCreateDTO, User user){
         this.name = categoryCreateDTO.getName();
         this.colorCode = categoryCreateDTO.getColorCode();
diff --git a/src/main/java/com/trendithon/timetris/domain/mainpage/domain/Plan.java b/src/main/java/com/trendithon/timetris/domain/mainpage/domain/Plan.java
index 3a5fe6c..556fb82 100644
--- a/src/main/java/com/trendithon/timetris/domain/mainpage/domain/Plan.java
+++ b/src/main/java/com/trendithon/timetris/domain/mainpage/domain/Plan.java
@@ -18,17 +18,24 @@ public class Plan {
 
     @Id @GeneratedValue(strategy = GenerationType.IDENTITY)
     private long id;
+
     private String title;
+
     private LocalTime startTime;
+
     private LocalTime endTime;
+
     private boolean status;
+
     @ManyToOne(fetch = FetchType.LAZY)
     @JoinColumn(name = "categoryId")
     private Category category;
+
     @ManyToOne(fetch = FetchType.LAZY)
     @JoinColumn(name = "userDateId")
     private UserDate userDate;
-    @OneToMany(mappedBy = "plan", cascade = CascadeType.ALL)
+
+    @OneToMany(mappedBy = "plan", cascade = CascadeType.ALL, orphanRemoval = true)
     private List<Cycle> cycle;
 
     public Plan(PlanCreateDTO planCreateDTO, UserDate userDate){
diff --git a/src/main/java/com/trendithon/timetris/domain/mainpage/domain/UserDate.java b/src/main/java/com/trendithon/timetris/domain/mainpage/domain/UserDate.java
index dac6a43..37a441d 100644
--- a/src/main/java/com/trendithon/timetris/domain/mainpage/domain/UserDate.java
+++ b/src/main/java/com/trendithon/timetris/domain/mainpage/domain/UserDate.java
@@ -8,6 +8,9 @@
 import lombok.Getter;
 import lombok.NoArgsConstructor;
 
+import java.util.ArrayList;
+import java.util.List;
+
 
 @Entity
 @Getter
@@ -17,13 +20,24 @@ public class UserDate {
 
     @Id @GeneratedValue(strategy = GenerationType.IDENTITY)
     private long id;
+
     @ManyToOne(fetch = FetchType.LAZY)
     @JoinColumn(name = "userId")
     private User user;
+
     @ManyToOne(fetch = FetchType.LAZY)
     @JoinColumn(name = "dateId")
     private Date date;
 
+    @OneToMany(mappedBy = "userDate", cascade = CascadeType.ALL, orphanRemoval = true)
+    private List<Do> doList = new ArrayList<>();
+
+    @OneToMany(mappedBy = "userDate", cascade = CascadeType.ALL, orphanRemoval = true)
+    private List<Plan> planList = new ArrayList<>();
+
+    @OneToMany(mappedBy = "userDate", cascade = CascadeType.ALL, orphanRemoval = true)
+    private List<See> seeList = new ArrayList<>();
+
     public UserDate(UserDateCreateDTO userDateCreateDTO){
         this.user = userDateCreateDTO.getUser();
         this.date = userDateCreateDTO.getDate();
diff --git a/src/main/java/com/trendithon/timetris/domain/member/controller/MyPageController.java b/src/main/java/com/trendithon/timetris/domain/member/controller/MyPageController.java
index a4a41fb..6a7ba64 100644
--- a/src/main/java/com/trendithon/timetris/domain/member/controller/MyPageController.java
+++ b/src/main/java/com/trendithon/timetris/domain/member/controller/MyPageController.java
@@ -41,4 +41,12 @@ public ApiResponse<MyPageResponse.getMyPageDTO> updateName(@RequestBody UpdateNa
         return ApiResponse.success(SuccessStatus.OK, myPageDTO);
 
     }
+
+    @PostMapping
+    @Operation(summary = "회원 탈퇴 API")
+    public ApiResponse<?> userOutService(HttpServletRequest request) {
+        Long userId = tokenProvider.getUserId(request);
+        myPageService.deleteUser(userId);
+        return ApiResponse.success(SuccessStatus.DELETE_USER_SUCCESS);
+    }
 }
diff --git a/src/main/java/com/trendithon/timetris/domain/member/domain/User.java b/src/main/java/com/trendithon/timetris/domain/member/domain/User.java
index b28caf6..2039938 100644
--- a/src/main/java/com/trendithon/timetris/domain/member/domain/User.java
+++ b/src/main/java/com/trendithon/timetris/domain/member/domain/User.java
@@ -1,9 +1,14 @@
 package com.trendithon.timetris.domain.member.domain;
 
+import com.trendithon.timetris.domain.mainpage.domain.Category;
+import com.trendithon.timetris.domain.mainpage.domain.UserDate;
 import jakarta.persistence.*;
 import jakarta.validation.constraints.NotNull;
 import lombok.*;
 
+import java.util.ArrayList;
+import java.util.List;
+
 @Entity
 @Getter
 @Builder
@@ -31,6 +36,12 @@ public class User {
 
     private String refreshToken;
 
+    @OneToMany(mappedBy = "user", cascade = CascadeType.ALL, orphanRemoval = true)
+    private List<Category> categories = new ArrayList<>();
+
+    @OneToMany(mappedBy = "user", cascade = CascadeType.ALL, orphanRemoval = true)
+    private List<UserDate> userDateList = new ArrayList<>();
+
     public void changeNickname(String nickname) {
         this.nickname = nickname;
     }
diff --git a/src/main/java/com/trendithon/timetris/domain/member/service/MyPageService.java b/src/main/java/com/trendithon/timetris/domain/member/service/MyPageService.java
index ccebc21..5121ec9 100644
--- a/src/main/java/com/trendithon/timetris/domain/member/service/MyPageService.java
+++ b/src/main/java/com/trendithon/timetris/domain/member/service/MyPageService.java
@@ -4,8 +4,6 @@
 import com.trendithon.timetris.domain.member.dto.MyPageResponse;
 import com.trendithon.timetris.domain.member.dto.UpdateNameRequest;
 import com.trendithon.timetris.domain.member.repository.UserRepository;
-import com.trendithon.timetris.global.exception.CustomException;
-import com.trendithon.timetris.global.exception.enums.ErrorStatus;
 import lombok.RequiredArgsConstructor;
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
@@ -41,5 +39,10 @@ public MyPageResponse.getMyPageDTO updateName(Long userId, UpdateNameRequest nam
                 .build();
 
     }
+    @Transactional
+    public void deleteUser(Long userId) {
+        userRepository.deleteById(userId);
+
+    }
 
 }
diff --git a/src/main/java/com/trendithon/timetris/global/auth/oauth/handler/OAuth2SuccessHandler.java b/src/main/java/com/trendithon/timetris/global/auth/oauth/handler/OAuth2SuccessHandler.java
index 5e586f3..0b6be4f 100644
--- a/src/main/java/com/trendithon/timetris/global/auth/oauth/handler/OAuth2SuccessHandler.java
+++ b/src/main/java/com/trendithon/timetris/global/auth/oauth/handler/OAuth2SuccessHandler.java
@@ -12,7 +12,6 @@
 import org.springframework.security.web.authentication.SimpleUrlAuthenticationSuccessHandler;
 import org.springframework.stereotype.Component;
 import org.springframework.transaction.annotation.Transactional;
-import org.springframework.web.util.UriComponentsBuilder;
 
 import java.io.IOException;
 
diff --git a/src/main/java/com/trendithon/timetris/global/exception/enums/SuccessStatus.java b/src/main/java/com/trendithon/timetris/global/exception/enums/SuccessStatus.java
index 82771b2..9b43b97 100644
--- a/src/main/java/com/trendithon/timetris/global/exception/enums/SuccessStatus.java
+++ b/src/main/java/com/trendithon/timetris/global/exception/enums/SuccessStatus.java
@@ -12,7 +12,8 @@ public enum SuccessStatus {
     /**
      * 200 OK
      */
-    OK(HttpStatus.OK, "COMMON200", "성공입니다.");
+    OK(HttpStatus.OK, "COMMON200", "성공입니다."),
+    DELETE_USER_SUCCESS(HttpStatus.OK, "USER200", "유저 탈퇴 성공입니다.");
 
     private final HttpStatus httpStatus;
     private final String code;