diff --git a/src/main/java/com/example/ReMap/domain/auth/entity/RefreshToken.java b/src/main/java/com/example/ReMap/domain/auth/entity/RefreshToken.java
index e4ac48f..9517ca0 100644
--- a/src/main/java/com/example/ReMap/domain/auth/entity/RefreshToken.java
+++ b/src/main/java/com/example/ReMap/domain/auth/entity/RefreshToken.java
@@ -1,77 +1,45 @@
 package com.example.ReMap.domain.auth.entity;
 
-
 import com.example.ReMap.domain.member.Member;
 import jakarta.persistence.*;
+import lombok.*;
 import java.time.LocalDateTime;
 
-
 @Entity
 @Table(name = "refresh_token")
+@Getter @Setter
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
+@AllArgsConstructor
+@Builder
 public class RefreshToken {
 
     @Id
     @GeneratedValue(strategy = GenerationType.IDENTITY)
     private Long id;
 
-    @OneToOne(fetch = FetchType.LAZY)
-    @JoinColumn(name = "member_id", nullable = false)
+    // Member 삭제 시 토큰도 함께 삭제
+    @OneToOne(fetch = FetchType.LAZY, optional = false, cascade = CascadeType.REMOVE)
+    @JoinColumn(name = "member_id", nullable = false, unique = true)
     private Member member;
 
-    @Column(name = "refresh_token", nullable = false)
+    @Column(name = "refresh_token", nullable = false, length = 512)
     private String refreshToken;
 
-    @Column(name = "created_at")
+    @Column(name = "created_at", nullable = false)
     private LocalDateTime createdAt;
 
-    @Column(name = "updated_at")
+    @Column(name = "updated_at", nullable = false)
     private LocalDateTime updatedAt;
 
-    // 기본 생성자
-    public RefreshToken() {}
-
-    // 생성자
-    public RefreshToken(Member member, String refreshToken, LocalDateTime createdAt, LocalDateTime updatedAt) {
-        this.member = member;
-        this.refreshToken = refreshToken;
-        this.createdAt = createdAt;
-        this.updatedAt = updatedAt;
-    }
-
-    // Getter / Setter
-    public Long getId() {
-        return id;
-    }
-
-    public Member getMember() {
-        return member;
-    }
-
-    public void setMember(Member member) {
-        this.member = member;
-    }
-
-    public String getRefreshToken() {
-        return refreshToken;
-    }
-
-    public void setRefreshToken(String refreshToken) {
-        this.refreshToken = refreshToken;
-    }
-
-    public LocalDateTime getCreatedAt() {
-        return createdAt;
-    }
-
-    public void setCreatedAt(LocalDateTime createdAt) {
-        this.createdAt = createdAt;
-    }
-
-    public LocalDateTime getUpdatedAt() {
-        return updatedAt;
+    @PrePersist
+    public void prePersist() {
+        LocalDateTime now = LocalDateTime.now();
+        this.createdAt = now;
+        this.updatedAt = now;
     }
 
-    public void setUpdatedAt(LocalDateTime updatedAt) {
-        this.updatedAt = updatedAt;
+    @PreUpdate
+    public void preUpdate() {
+        this.updatedAt = LocalDateTime.now();
     }
 }
diff --git a/src/main/java/com/example/ReMap/domain/cast/Cast.java b/src/main/java/com/example/ReMap/domain/cast/Cast.java
index 9d26661..cbc9608 100644
--- a/src/main/java/com/example/ReMap/domain/cast/Cast.java
+++ b/src/main/java/com/example/ReMap/domain/cast/Cast.java
@@ -1,6 +1,7 @@
 package com.example.ReMap.domain.cast;
 
 import com.example.ReMap.domain.member.Member;
+import com.fasterxml.jackson.annotation.JsonIgnore;
 import jakarta.persistence.*;
 
 import java.time.LocalDateTime;
@@ -20,6 +21,7 @@ public class Cast {
 
     @ManyToOne
     @JoinColumn(name = "member_id")
+    @JsonIgnore
     private Member member;
 
     // 생성자, getter, setter
diff --git a/src/main/java/com/example/ReMap/domain/cast/CastRepository.java b/src/main/java/com/example/ReMap/domain/cast/CastRepository.java
new file mode 100644
index 0000000..fdd667d
--- /dev/null
+++ b/src/main/java/com/example/ReMap/domain/cast/CastRepository.java
@@ -0,0 +1,12 @@
+package com.example.ReMap.domain.cast;
+
+
+import org.springframework.data.jpa.repository.JpaRepository;
+
+/**
+ * Cast(게시글) 전용 JPA 레포지토리
+ * → JpaRepository 를 상속하면 findById, save, delete 등 기본 메서드가 자동 생성됩니다.
+ */
+public interface CastRepository extends JpaRepository<Cast, Long> {
+    // 필요하면 여기에 커스텀 쿼리 메서드 추가
+}
diff --git a/src/main/java/com/example/ReMap/domain/comment/Comment.java b/src/main/java/com/example/ReMap/domain/comment/Comment.java
index fbe0ae1..d5419ba 100644
--- a/src/main/java/com/example/ReMap/domain/comment/Comment.java
+++ b/src/main/java/com/example/ReMap/domain/comment/Comment.java
@@ -2,27 +2,50 @@
 
 import com.example.ReMap.domain.cast.Cast;
 import com.example.ReMap.domain.member.Member;
+import com.fasterxml.jackson.annotation.JsonIgnore;
 import jakarta.persistence.*;
+import lombok.*;
+import org.hibernate.annotations.CreationTimestamp;
 
 import java.time.LocalDateTime;
 
 @Entity
 @Table(name = "comment")
+@Getter
+@Setter                              // 전체 Setter 허용
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
+@AllArgsConstructor
+@Builder
 public class Comment {
-    @Id
-    @GeneratedValue(strategy = GenerationType.IDENTITY)
+
+    @Id @GeneratedValue(strategy = GenerationType.IDENTITY)
     private Long id;
 
+    /** VARCHAR(255) 에 맞춤 */
+    @Column(length = 255, nullable = false)
     private String content;
 
+    /** 생성 시각 – DB 기본값 대신 애플리케이션에서 채움 */
+    @CreationTimestamp
+    @Column(name = "created_at")
     private LocalDateTime createdAt;
 
-    @ManyToOne
+    /* ---------- 연관 관계 ---------- */
+
+    /** 작성자 – DDL이 NULL 허용 → optional = true */
+    @ManyToOne(fetch = FetchType.LAZY, optional = true)
     @JoinColumn(name = "member_id")
+    @JsonIgnore
     private Member member;
 
-    @ManyToOne
+    /** 대상 캐스트 – DDL이 NULL 허용 → optional = true */
+    @ManyToOne(fetch = FetchType.LAZY, optional = true)
     @JoinColumn(name = "cast_id")
     private Cast cast;
-}
 
+    /* ---------- 도메인 메서드 ---------- */
+
+    public void changeContent(String newContent) {
+        this.content = newContent;
+    }
+}
diff --git a/src/main/java/com/example/ReMap/domain/comment/CommentController.java b/src/main/java/com/example/ReMap/domain/comment/CommentController.java
new file mode 100644
index 0000000..869babc
--- /dev/null
+++ b/src/main/java/com/example/ReMap/domain/comment/CommentController.java
@@ -0,0 +1,64 @@
+package com.example.ReMap.domain.comment;
+
+import com.example.ReMap.domain.comment.CommentService;
+import com.example.ReMap.domain.comment.dto.CommentResponse;
+import com.example.ReMap.domain.comment.dto.CreateCommentRequest;
+import com.example.ReMap.domain.comment.dto.UpdateCommentRequest;
+import jakarta.validation.Valid;
+import lombok.RequiredArgsConstructor;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.*;
+
+import java.security.Principal;
+import java.util.List;
+
+@RestController
+@RequestMapping("/casts/{castId}/comments")
+@RequiredArgsConstructor
+public class CommentController {
+
+    private final CommentService commentService;
+
+    /* ------------------------------------ 1. 댓글 등록 ------------------------------------ */
+    @PostMapping
+    public ResponseEntity<CommentResponse> create(
+            @PathVariable Long castId,
+            @RequestBody @Valid CreateCommentRequest req,
+            Principal principal            // 로그인 사용자 정보(아이디 문자열)
+    ) {
+        Long memberId = Long.valueOf(principal.getName());   // "1" → 1L 등으로 변환
+        CommentResponse resp = commentService.create(castId, memberId, req.getContent());
+        return ResponseEntity.status(HttpStatus.CREATED).body(resp);
+    }
+
+    /* ------------------------------------ 2. 댓글 목록 ------------------------------------ */
+    @GetMapping
+    public List<CommentResponse> list(@PathVariable Long castId) {
+        return commentService.list(castId);
+    }
+
+    /* ------------------------------------ 3. 댓글 수정 ------------------------------------ */
+    @PutMapping("/{commentId}")
+    public CommentResponse update(
+            @PathVariable Long castId,      // 경로 일관성 확보용
+            @PathVariable Long commentId,
+            @RequestBody @Valid UpdateCommentRequest req,
+            Principal principal
+    ) {
+        Long memberId = Long.valueOf(principal.getName());
+        return commentService.update(commentId, memberId, req.getContent());
+    }
+
+    /* ------------------------------------ 4. 댓글 삭제 ------------------------------------ */
+    @DeleteMapping("/{commentId}")
+    public ResponseEntity<Void> delete(
+            @PathVariable Long castId,
+            @PathVariable Long commentId,
+            Principal principal
+    ) {
+        Long memberId = Long.valueOf(principal.getName());
+        commentService.delete(commentId, memberId);
+        return ResponseEntity.noContent().build();
+    }
+}
diff --git a/src/main/java/com/example/ReMap/domain/comment/CommentRepository.java b/src/main/java/com/example/ReMap/domain/comment/CommentRepository.java
new file mode 100644
index 0000000..030a246
--- /dev/null
+++ b/src/main/java/com/example/ReMap/domain/comment/CommentRepository.java
@@ -0,0 +1,21 @@
+package com.example.ReMap.domain.comment;
+
+
+import org.springframework.data.jpa.repository.EntityGraph;
+import org.springframework.data.jpa.repository.JpaRepository;
+
+import java.util.List;
+
+/**
+ * 댓글 레포지토리
+ *
+ * • findByCastIdOrderByCreatedAtAsc()  :   특정 Cast(게시글)의 댓글을
+ *   작성 시간순으로 가져옵니다.
+ * • @EntityGraph("member")            :   댓글과 작성자를 한 번에 로딩해서
+ *   N+1 쿼리 문제를 예방합니다.
+ */
+public interface CommentRepository extends JpaRepository<Comment, Long> {
+
+    @EntityGraph(attributePaths = "member")      // 댓글 조회 + Member 한 번에 가져오기
+    List<Comment> findByCastIdOrderByCreatedAtAsc(Long castId);
+}
diff --git a/src/main/java/com/example/ReMap/domain/comment/CommentService.java b/src/main/java/com/example/ReMap/domain/comment/CommentService.java
new file mode 100644
index 0000000..bfa65c2
--- /dev/null
+++ b/src/main/java/com/example/ReMap/domain/comment/CommentService.java
@@ -0,0 +1,91 @@
+package com.example.ReMap.domain.comment;
+
+
+import com.example.ReMap.domain.cast.Cast;
+import com.example.ReMap.domain.comment.Comment;
+import com.example.ReMap.domain.comment.CommentRepository;
+import com.example.ReMap.domain.member.Member;
+import com.example.ReMap.domain.member.MemberRepository;
+import com.example.ReMap.domain.comment.dto.CommentResponse;
+import jakarta.transaction.Transactional;
+import lombok.RequiredArgsConstructor;
+import org.springframework.security.access.AccessDeniedException;
+import org.springframework.stereotype.Service;
+
+import java.util.List;
+
+@Service
+@RequiredArgsConstructor          // 의존성 주입용 생성자 자동
+@Transactional                    // 메서드 기본 read-write
+public class CommentService {
+
+    private final CommentRepository commentRepo;
+    private final com.example.ReMap.domain.cast.CastRepository castRepo;
+    private final MemberRepository  memberRepo;
+
+    /* ---------- CREATE ---------- */
+
+    public CommentResponse create(Long castId, Long memberId, String content) {
+
+        Cast cast = castRepo.findById(castId)
+                .orElseThrow(() -> new IllegalArgumentException("Cast not found : " + castId));
+
+        Member member = memberRepo.findById(memberId)
+                .orElseThrow(() -> new IllegalArgumentException("Member not found : " + memberId));
+
+        // 댓글 엔티티 생성
+        Comment comment = Comment.builder()
+                .content(content)
+                .build();
+
+        // FK 세팅 (엔티티 @Setter 덕분에 가능)
+        comment.setCast(cast);
+        comment.setMember(member);
+
+        // 저장
+        commentRepo.save(comment);
+
+        return CommentResponse.from(comment);
+    }
+
+    /* ---------- READ (목록) ---------- */
+    @Transactional(Transactional.TxType.SUPPORTS)   // read-only 트랜잭션
+    public List<CommentResponse> list(Long castId) {
+        return commentRepo.findByCastIdOrderByCreatedAtAsc(castId)
+                .stream()
+                .map(CommentResponse::from)
+                .toList();
+    }
+
+    /* ---------- UPDATE ---------- */
+
+    public CommentResponse update(Long commentId, Long requesterId, String newContent) {
+
+        Comment comment = commentRepo.findById(commentId)
+                .orElseThrow(() -> new IllegalArgumentException("Comment not found : " + commentId));
+
+        // 작성자 권한 확인
+        if (!requesterId.equals(comment.getMember() != null ? comment.getMember().getId() : null)) {
+            throw new AccessDeniedException("본인 댓글만 수정할 수 있습니다.");
+        }
+
+        comment.changeContent(newContent);   // 엔티티 내부에서 필드 변경
+
+        return CommentResponse.from(comment);
+    }
+
+    /* ---------- DELETE ---------- */
+
+    public void delete(Long commentId, Long requesterId) {
+
+        Comment comment = commentRepo.findById(commentId)
+                .orElseThrow(() -> new IllegalArgumentException("Comment not found : " + commentId));
+
+        if (!requesterId.equals(comment.getMember() != null ? comment.getMember().getId() : null)) {
+            throw new AccessDeniedException("본인 댓글만 삭제할 수 있습니다.");
+        }
+
+        commentRepo.delete(comment);          // 하드 삭제
+        // → 소프트 삭제가 필요하면 Comment에 deleted 필드를 추가해 플래그만 변경
+    }
+}
diff --git a/src/main/java/com/example/ReMap/domain/comment/dto/CommentResponse.java b/src/main/java/com/example/ReMap/domain/comment/dto/CommentResponse.java
new file mode 100644
index 0000000..2ecd9e2
--- /dev/null
+++ b/src/main/java/com/example/ReMap/domain/comment/dto/CommentResponse.java
@@ -0,0 +1,31 @@
+package com.example.ReMap.domain.comment.dto;
+
+
+import com.example.ReMap.domain.comment.Comment;
+import lombok.Builder;
+import lombok.Getter;
+
+import java.time.LocalDateTime;
+
+/** 댓글 단건 응답 DTO */
+@Getter
+@Builder
+public class CommentResponse {
+
+    private Long id;               // 댓글 ID
+    private Long memberId;         // 작성자 ID
+    private String nickname;       // 작성자 닉네임
+    private String content;        // 댓글 본문
+    private LocalDateTime createdAt;
+
+    /** Comment 엔티티 → DTO 변환 */
+    public static CommentResponse from(Comment c) {
+        return CommentResponse.builder()
+                .id(c.getId())
+                .memberId(c.getMember() != null ? c.getMember().getId() : null)
+                .nickname(c.getMember() != null ? c.getMember().getNickname() : "탈퇴한 회원")
+                .content(c.getContent())
+                .createdAt(c.getCreatedAt())
+                .build();
+    }
+}
diff --git a/src/main/java/com/example/ReMap/domain/comment/dto/CreateCommentRequest.java b/src/main/java/com/example/ReMap/domain/comment/dto/CreateCommentRequest.java
new file mode 100644
index 0000000..70c9023
--- /dev/null
+++ b/src/main/java/com/example/ReMap/domain/comment/dto/CreateCommentRequest.java
@@ -0,0 +1,16 @@
+package com.example.ReMap.domain.comment.dto;
+
+
+import jakarta.validation.constraints.NotBlank;
+import lombok.Getter;
+import lombok.Setter;
+
+/** 댓글 등록 요청 DTO */
+@Getter @Setter
+public class CreateCommentRequest {
+
+    /** 댓글 본문 (빈 문자열 금지) */
+    @NotBlank(message = "댓글 내용을 입력해 주세요.")
+    private String content;
+}
+
diff --git a/src/main/java/com/example/ReMap/domain/comment/dto/UpdateCommentRequest.java b/src/main/java/com/example/ReMap/domain/comment/dto/UpdateCommentRequest.java
new file mode 100644
index 0000000..685cb4e
--- /dev/null
+++ b/src/main/java/com/example/ReMap/domain/comment/dto/UpdateCommentRequest.java
@@ -0,0 +1,16 @@
+package com.example.ReMap.domain.comment.dto;
+
+
+import jakarta.validation.constraints.NotBlank;
+import lombok.Getter;
+import lombok.Setter;
+
+/** 댓글 수정 요청 DTO */
+@Getter @Setter
+public class UpdateCommentRequest {
+
+    /** 수정할 댓글 본문 */
+    @NotBlank(message = "댓글 내용을 입력해 주세요.")
+    private String content;
+}
+
diff --git a/src/main/java/com/example/ReMap/domain/member/ChangeMemberTypeRequest.java b/src/main/java/com/example/ReMap/domain/member/ChangeMemberTypeRequest.java
new file mode 100644
index 0000000..d694584
--- /dev/null
+++ b/src/main/java/com/example/ReMap/domain/member/ChangeMemberTypeRequest.java
@@ -0,0 +1,17 @@
+package com.example.ReMap.domain.member;
+
+import jakarta.validation.constraints.NotNull;
+
+public class ChangeMemberTypeRequest {
+
+    @NotNull(message = "회원 유형을 선택해주세요.")
+    private MemberType memberType;
+
+    public MemberType getMemberType() {
+        return memberType;
+    }
+
+    public void setMemberType(MemberType memberType) {
+        this.memberType = memberType;
+    }
+}
diff --git a/src/main/java/com/example/ReMap/domain/member/ChangePasswordRequest.java b/src/main/java/com/example/ReMap/domain/member/ChangePasswordRequest.java
new file mode 100644
index 0000000..fb54dd5
--- /dev/null
+++ b/src/main/java/com/example/ReMap/domain/member/ChangePasswordRequest.java
@@ -0,0 +1,15 @@
+package com.example.ReMap.domain.member;
+
+import jakarta.validation.constraints.NotBlank;
+import lombok.Getter;
+import lombok.Setter;
+
+@Getter @Setter
+public class ChangePasswordRequest {
+
+    @NotBlank(message = "현재 비밀번호를 입력해주세요.")
+    private String currentPassword;
+
+    @NotBlank(message = "새 비밀번호를 입력해주세요.")
+    private String newPassword;
+}
diff --git a/src/main/java/com/example/ReMap/domain/member/Member.java b/src/main/java/com/example/ReMap/domain/member/Member.java
index 7e4f49e..8a88908 100644
--- a/src/main/java/com/example/ReMap/domain/member/Member.java
+++ b/src/main/java/com/example/ReMap/domain/member/Member.java
@@ -2,32 +2,25 @@
 
 import com.example.ReMap.domain.cast.Cast;
 import com.example.ReMap.domain.comment.Comment;
-import com.example.ReMap.domain.auth.entity.RefreshToken;
-import com.example.ReMap.domain.member.MemberType;
+import com.fasterxml.jackson.annotation.JsonIgnore;
 import jakarta.persistence.*;
 import lombok.*;
 
-import java.time.LocalDateTime;
 import java.util.ArrayList;
 import java.util.List;
 
 @Entity
 @Getter
-@Builder
-@AllArgsConstructor
+@Setter
 @NoArgsConstructor(access = AccessLevel.PROTECTED)
+@AllArgsConstructor
+@Builder
 @Table(name = "member")
 public class Member {
 
-    @Id
-    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    @Id @GeneratedValue(strategy = GenerationType.IDENTITY)
     private Long id;
 
-    @Column(nullable = false)
-    private String password;
-
-    private Integer phone;
-
     private Long birth;
 
     @Column(unique = true)
@@ -36,24 +29,20 @@ public class Member {
     @Column(nullable = false, unique = true)
     private String nickname;
 
-    @Column(name = "inactive_date")
-    private LocalDateTime inactiveDate;
-
-    @Column(name = "created_at")
-    private LocalDateTime createdAt;
-
-    @Column(name = "updated_at")
-    private LocalDateTime updatedAt;
-
+    @Builder.Default
     @Enumerated(EnumType.STRING)
-    @Column(name = "memberType")
-    private MemberType memberType = MemberType.GENERAL;
+    @Column(name = "member_type")
+    private MemberType memberType = MemberType.USER;
 
-    // 관계 매핑
+    // 내가 올린 오디오
     @OneToMany(mappedBy = "member", cascade = CascadeType.ALL, orphanRemoval = true)
+    @JsonIgnore
+    @Builder.Default
     private List<Cast> casts = new ArrayList<>();
 
+    // 내가 쓴 댓글
     @OneToMany(mappedBy = "member", cascade = CascadeType.ALL, orphanRemoval = true)
+    @JsonIgnore
+    @Builder.Default
     private List<Comment> comments = new ArrayList<>();
-
-    }
+}
diff --git a/src/main/java/com/example/ReMap/domain/member/MemberController.java b/src/main/java/com/example/ReMap/domain/member/MemberController.java
new file mode 100644
index 0000000..6703c8a
--- /dev/null
+++ b/src/main/java/com/example/ReMap/domain/member/MemberController.java
@@ -0,0 +1,74 @@
+package com.example.ReMap.domain.member;
+
+import com.example.ReMap.domain.cast.Cast;
+import com.example.ReMap.domain.comment.Comment;
+import com.example.ReMap.domain.auth.util.JwtUtil;  // 실제 JwtUtil 위치에 맞춰 수정
+import jakarta.validation.Valid;
+import lombok.RequiredArgsConstructor;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.*;
+
+import java.util.List;
+
+@RestController
+@RequestMapping("/api/members")
+@RequiredArgsConstructor
+public class MemberController {
+
+    private final MemberService memberService;
+    private final JwtUtil jwtUtil;
+
+    /** 내 정보 조회 **/
+    @GetMapping("/setting")
+    public ResponseEntity<Member> getMember(
+            @RequestHeader("Authorization") String authorization) {
+        Long memberId = jwtUtil.extractMemberId(authorization);
+        return ResponseEntity.ok(memberService.getMemberById(memberId));
+    }
+
+    /** 내 정보 수정 **/
+    @PutMapping("/update")
+    public ResponseEntity<Member> updateMember(
+            @RequestHeader("Authorization") String authorization,
+            @Valid @RequestBody UpdateMemberRequest req) {
+        Long memberId = jwtUtil.extractMemberId(authorization);
+        return ResponseEntity.ok(memberService.updateMember(memberId, req));
+    }
+
+    /** 비밀번호 변경 **/
+    @PutMapping("/password")
+    public ResponseEntity<Void> changePassword(
+            @RequestHeader("Authorization") String authorization,
+            @Valid @RequestBody ChangePasswordRequest req) {
+        Long memberId = jwtUtil.extractMemberId(authorization);
+        memberService.changePassword(memberId, req);
+        return ResponseEntity.ok().build();
+    }
+
+    /** 내가 쓴 댓글 목록 **/
+    @GetMapping("/comments")
+    public ResponseEntity<List<Comment>> getComments(
+            @RequestHeader("Authorization") String authorization) {
+        Long memberId = jwtUtil.extractMemberId(authorization);
+        return ResponseEntity.ok(memberService.getMemberComments(memberId));
+    }
+
+    /** 내가 올린 오디오 목록 **/
+    @GetMapping("/casts")
+    public ResponseEntity<List<Cast>> getCasts(
+            @RequestHeader("Authorization") String authorization) {
+        Long memberId = jwtUtil.extractMemberId(authorization);
+        return ResponseEntity.ok(memberService.getMemberCasts(memberId));
+    }
+
+    /** USER ↔ RECORDER 역할 전환 **/
+    @PutMapping("/member-type")
+    public ResponseEntity<Member> changeRole(
+            @RequestHeader("Authorization") String authorization,
+            @Valid @RequestBody ChangeMemberTypeRequest req) {
+        Long memberId = jwtUtil.extractMemberId(authorization);
+        return ResponseEntity.ok(
+                memberService.changeOwnRole(memberId, req.getMemberType())
+        );
+    }
+}
diff --git a/src/main/java/com/example/ReMap/domain/member/MemberRepository.java b/src/main/java/com/example/ReMap/domain/member/MemberRepository.java
new file mode 100644
index 0000000..39cec94
--- /dev/null
+++ b/src/main/java/com/example/ReMap/domain/member/MemberRepository.java
@@ -0,0 +1,10 @@
+package com.example.ReMap.domain.member;
+
+import org.springframework.data.jpa.repository.JpaRepository;
+
+import java.util.Optional;
+
+public interface MemberRepository extends JpaRepository<Member, Long> {
+    boolean existsByNickname(String nickname);
+}
+
diff --git a/src/main/java/com/example/ReMap/domain/member/MemberService.java b/src/main/java/com/example/ReMap/domain/member/MemberService.java
new file mode 100644
index 0000000..a90f14d
--- /dev/null
+++ b/src/main/java/com/example/ReMap/domain/member/MemberService.java
@@ -0,0 +1,78 @@
+package com.example.ReMap.domain.member;
+
+import com.example.ReMap.domain.cast.Cast;
+import com.example.ReMap.domain.comment.Comment;
+import jakarta.persistence.EntityNotFoundException;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.util.List;
+
+@Service
+@RequiredArgsConstructor
+@Transactional
+public class MemberService {
+
+    private final MemberRepository memberRepository;
+
+    /* -------------------------- Read (조회) ----------------------------- */
+
+    @Transactional(readOnly = true)
+    public Member getMemberById(Long id) {
+        return memberRepository.findById(id)
+                .orElseThrow(() -> new EntityNotFoundException("회원을 찾을 수 없습니다. ID: " + id));
+    }
+
+    @Transactional(readOnly = true)
+    public List<Comment> getMemberComments(Long memberId) {
+        return getMemberById(memberId).getComments();
+    }
+
+    @Transactional(readOnly = true)
+    public List<Cast> getMemberCasts(Long memberId) {
+        Member member = getMemberById(memberId);
+        // USER도 자신의 캐스트(업로드)를 볼 수 있게 하려면 아래 검사를 제거하세요.
+        if (member.getMemberType() != MemberType.RECORDER && member.getMemberType() != MemberType.ADMIN) {
+            throw new IllegalArgumentException("기록자만 오디오 목록을 조회할 수 있습니다.");
+        }
+        return member.getCasts();
+    }
+
+    /* -------------------------- Update (수정) --------------------------- */
+
+    public Member updateMember(Long id, UpdateMemberRequest dto) {
+        Member member = getMemberById(id);
+
+        // 닉네임 변경 시 중복 검사
+        if (dto.getNickname() != null && !dto.getNickname().equals(member.getNickname())
+                && memberRepository.existsByNickname(dto.getNickname())) {
+            throw new IllegalArgumentException("이미 사용 중인 닉네임입니다.");
+        }
+        member.setNickname(dto.getNickname());
+
+        // 생년월일 업데이트
+        member.setBirth(dto.getBirth());
+
+        return member;
+    }
+
+    /* ----------------------- Role Self-Change -------------------------- */
+
+    /**
+     * 본인이 USER ↔ RECORDER 로만 스스로 타입 변경
+     */
+    public Member changeOwnRole(Long id, MemberType newType) {
+        Member member = getMemberById(id);
+
+        if (newType != MemberType.USER && newType != MemberType.RECORDER) {
+            throw new IllegalArgumentException("변경 가능한 역할은 USER 또는 RECORDER 뿐입니다.");
+        }
+
+        member.setMemberType(newType);
+        return member;
+    }
+
+
+
+}
diff --git a/src/main/java/com/example/ReMap/domain/member/MemberType.java b/src/main/java/com/example/ReMap/domain/member/MemberType.java
index 825c576..a9c7812 100644
--- a/src/main/java/com/example/ReMap/domain/member/MemberType.java
+++ b/src/main/java/com/example/ReMap/domain/member/MemberType.java
@@ -1,6 +1,17 @@
 package com.example.ReMap.domain.member;
 
 public enum MemberType {
-    GENERAL,   // 일반 유저
-    RECORDER   // 기록자
-}
+    USER("일반유저"),        // 오디오 감상, 감상후기 작성
+    RECORDER("기록자"),      // 음성파일 업로드
+    ADMIN("관리자");         // 전체 관리
+
+    private final String description;
+
+    MemberType(String description) {
+        this.description = description;
+    }
+
+    public String getDescription() {
+        return description;
+    }
+}
\ No newline at end of file
diff --git a/src/main/java/com/example/ReMap/domain/member/UpdateMemberRequest.java b/src/main/java/com/example/ReMap/domain/member/UpdateMemberRequest.java
new file mode 100644
index 0000000..5d17d2c
--- /dev/null
+++ b/src/main/java/com/example/ReMap/domain/member/UpdateMemberRequest.java
@@ -0,0 +1,18 @@
+package com.example.ReMap.domain.member;
+
+import jakarta.validation.constraints.*;
+import lombok.Getter;
+import lombok.Setter;
+
+@Getter
+@Setter
+public class UpdateMemberRequest {
+
+
+    @NotNull(message = "생년월일을 입력해 주세요.")
+    private Long birth;
+
+    @NotBlank(message = "닉네임을 입력해 주세요.")
+    @Size(max = 50, message = "닉네임은 최대 50자까지 가능합니다.")
+    private String nickname;
+}
diff --git a/src/main/java/com/example/ReMap/domain/tema/Tema.java b/src/main/java/com/example/ReMap/domain/tema/Tema.java
index e877d51..e8a505f 100644
--- a/src/main/java/com/example/ReMap/domain/tema/Tema.java
+++ b/src/main/java/com/example/ReMap/domain/tema/Tema.java
@@ -1,14 +1,29 @@
 package com.example.ReMap.domain.tema;
 
+import com.example.ReMap.domain.cast.Cast;
 import jakarta.persistence.*;
+import lombok.*;
+
+import java.util.ArrayList;
+import java.util.List;
 
 @Entity
 @Table(name = "tema")
+@Getter
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
 public class Tema {
-    @Id
-    @GeneratedValue(strategy = GenerationType.IDENTITY)
+
+    @Id @GeneratedValue(strategy = GenerationType.IDENTITY)
     private Long id;
 
+    @Column(nullable = false, length = 255)
     private String name;
-}
 
+    @ManyToMany(mappedBy = "temas")
+    private List<Cast> casts = new ArrayList<>();
+
+    @Builder          // name 하나만 받도록
+    public Tema(String name) {
+        this.name = name;
+    }
+}
diff --git a/src/main/java/com/example/ReMap/domain/tema/TemaController.java b/src/main/java/com/example/ReMap/domain/tema/TemaController.java
new file mode 100644
index 0000000..1cde3f7
--- /dev/null
+++ b/src/main/java/com/example/ReMap/domain/tema/TemaController.java
@@ -0,0 +1,4 @@
+package com.example.ReMap.domain.tema;
+
+public class TemaController {
+}
diff --git a/src/main/java/com/example/ReMap/domain/tema/TemaRepository.java b/src/main/java/com/example/ReMap/domain/tema/TemaRepository.java
new file mode 100644
index 0000000..5f89b6f
--- /dev/null
+++ b/src/main/java/com/example/ReMap/domain/tema/TemaRepository.java
@@ -0,0 +1,17 @@
+package com.example.ReMap.domain.tema;
+
+import org.springframework.data.jpa.repository.JpaRepository;
+
+import java.util.Optional;
+
+/**
+ * Tema(테마) 전용 레포지토리
+ * - findByName   : 이름으로 단건 조회
+ * - existsByName : 중복 이름 체크
+ */
+public interface TemaRepository extends JpaRepository<Tema, Long> {
+
+    Optional<Tema> findByName(String name);
+
+    boolean existsByName(String name);
+}
diff --git a/src/main/java/com/example/ReMap/domain/tema/dto/TemaCreateRequest.java b/src/main/java/com/example/ReMap/domain/tema/dto/TemaCreateRequest.java
new file mode 100644
index 0000000..7e33bcb
--- /dev/null
+++ b/src/main/java/com/example/ReMap/domain/tema/dto/TemaCreateRequest.java
@@ -0,0 +1,13 @@
+package com.example.ReMap.domain.tema.dto;
+
+import jakarta.validation.constraints.NotBlank;
+import lombok.Getter;
+import lombok.Setter;
+
+/** 테마 생성 요청 */
+@Getter @Setter
+public class TemaCreateRequest {
+
+    @NotBlank(message = "테마 이름을 입력해 주세요.")
+    private String name;
+}
diff --git a/src/main/java/com/example/ReMap/domain/tema/dto/TemaResponse.java b/src/main/java/com/example/ReMap/domain/tema/dto/TemaResponse.java
new file mode 100644
index 0000000..35340d5
--- /dev/null
+++ b/src/main/java/com/example/ReMap/domain/tema/dto/TemaResponse.java
@@ -0,0 +1,21 @@
+package com.example.ReMap.domain.tema.dto;
+
+import com.example.ReMap.domain.tema.Tema;
+import lombok.Builder;
+import lombok.Getter;
+
+/** 테마 단건 응답 DTO */
+@Getter
+@Builder
+public class TemaResponse {
+
+    private Long id;
+    private String name;
+
+    public static TemaResponse from(Tema t) {
+        return TemaResponse.builder()
+                .id(t.getId())
+                .name(t.getName())
+                .build();
+    }
+}
diff --git a/src/main/java/com/example/ReMap/domain/tema/dto/TemaUpdateRequest.java b/src/main/java/com/example/ReMap/domain/tema/dto/TemaUpdateRequest.java
new file mode 100644
index 0000000..fdc8c4a
--- /dev/null
+++ b/src/main/java/com/example/ReMap/domain/tema/dto/TemaUpdateRequest.java
@@ -0,0 +1,13 @@
+package com.example.ReMap.domain.tema.dto;
+
+import jakarta.validation.constraints.NotBlank;
+import lombok.Getter;
+import lombok.Setter;
+
+/** 테마 이름 수정 요청 */
+@Getter @Setter
+public class TemaUpdateRequest {
+
+    @NotBlank(message = "새 테마 이름을 입력해 주세요.")
+    private String name;
+}
diff --git a/src/main/resources/application.properties b/src/main/resources/application.properties
deleted file mode 100644
index 5bcf2fa..0000000
--- a/src/main/resources/application.properties
+++ /dev/null
@@ -1,22 +0,0 @@
-spring.application.name=ReMap
-# ?? ??
-server.port=8080
-
-# MySQL ?? ??
-spring.datasource.url=jdbc:mysql://localhost:3306/hackathon?serverTimezone=Asia/Seoul
-spring.datasource.username=root
-spring.datasource.password=1234
-spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
-
-# JPA ??
-spring.jpa.hibernate.ddl-auto=none
-spring.jpa.show-sql=true
-spring.jpa.properties.hibernate.format_sql=true
-spring.jpa.database-platform=org.hibernate.dialect.MySQL8Dialect
-
-# H2 ?? (???)
-spring.h2.console.enabled=true
-
-# ?? ?? (??)
-logging.level.org.hibernate.SQL=debug
-logging.level.org.hibernate.type=trace
diff --git a/src/main/resources/application.yml b/src/main/resources/application.yml
new file mode 100644
index 0000000..6970400
--- /dev/null
+++ b/src/main/resources/application.yml
@@ -0,0 +1,27 @@
+spring:
+  datasource:
+    url: jdbc:mysql://localhost:3306/hackathon?createDatabaseIfNotExist=TRUE&serverTimezone=Asia/Seoul&characterEncoding=UTF-8
+    username: root
+    password: 1234
+    driver-class-name: com.mysql.cj.jdbc.Driver
+  jpa:
+    hibernate:
+      ddl-auto: update
+    properties:
+      hibernate:
+        format_sql: true
+        show_sql: true
+
+springdoc:
+  swagger-ui:
+    path: /swagger-ui.html
+    operationsSorter: method
+    disable-swagger-default-url: true
+    display-request-duration: true
+  api-docs:
+    path: /api-docs
+  show-actuator: true
+  default-consumes-media-type: application/json
+  default-produces-media-type: application/json
+  paths-to-match:
+    - /api/**
\ No newline at end of file