diff --git a/src/main/java/com/neighbors/tohero/application/baseResponse/BaseResponseMessage.java b/src/main/java/com/neighbors/tohero/application/baseResponse/BaseResponseMessage.java
index a838556..016807f 100644
--- a/src/main/java/com/neighbors/tohero/application/baseResponse/BaseResponseMessage.java
+++ b/src/main/java/com/neighbors/tohero/application/baseResponse/BaseResponseMessage.java
@@ -48,6 +48,7 @@ public enum BaseResponseMessage {
     편지_생성이_실패_했습니다("편지 생성이 실패했습니다"),
     편지가_성공적으로_조회되었습니다("편지가 성공적으로 조회되었습니다"),
     일치하는_편지가_없습니다("일치하는 편지가 없습니다"),
+    편지_공개_여부가_수정되었습니다("편지 공개 여부가 수정되었습니다"),
 
     //news
     뉴스_조회가_성공했습니다("뉴스 조회가 성공했습니다"),
diff --git a/src/main/java/com/neighbors/tohero/application/letter/dto/UpdateLetterPublic.java b/src/main/java/com/neighbors/tohero/application/letter/dto/UpdateLetterPublic.java
new file mode 100644
index 0000000..def14a8
--- /dev/null
+++ b/src/main/java/com/neighbors/tohero/application/letter/dto/UpdateLetterPublic.java
@@ -0,0 +1,16 @@
+package com.neighbors.tohero.application.letter.dto;
+
+import jakarta.validation.constraints.Max;
+import jakarta.validation.constraints.Min;
+import jakarta.validation.constraints.NotNull;
+
+public record UpdateLetterPublic(
+    @NotNull
+    @Max(Long.MAX_VALUE)
+    @Min(0)
+    long letterId,
+
+    @NotNull
+    boolean isPublic
+) {
+}
diff --git a/src/main/java/com/neighbors/tohero/application/letter/dto/UpdateLetterPublicResponse.java b/src/main/java/com/neighbors/tohero/application/letter/dto/UpdateLetterPublicResponse.java
new file mode 100644
index 0000000..e608c0f
--- /dev/null
+++ b/src/main/java/com/neighbors/tohero/application/letter/dto/UpdateLetterPublicResponse.java
@@ -0,0 +1,11 @@
+package com.neighbors.tohero.application.letter.dto;
+
+public record UpdateLetterPublicResponse (
+        boolean before,
+        boolean after
+){
+
+    public static UpdateLetterPublicResponse of(boolean after) {
+        return new UpdateLetterPublicResponse(!after, after);
+    }
+}
diff --git a/src/main/java/com/neighbors/tohero/application/letter/service/LetterService.java b/src/main/java/com/neighbors/tohero/application/letter/service/LetterService.java
index 13d13c2..68c983d 100644
--- a/src/main/java/com/neighbors/tohero/application/letter/service/LetterService.java
+++ b/src/main/java/com/neighbors/tohero/application/letter/service/LetterService.java
@@ -10,8 +10,10 @@
 import com.neighbors.tohero.common.jwt.JwtUserDetails;
 import com.neighbors.tohero.domain.domain.address.service.GetAddress;
 import com.neighbors.tohero.domain.domain.letter.service.CreateLetter;
+import com.neighbors.tohero.domain.domain.letter.service.UpdateLetter;
 import com.neighbors.tohero.domain.domain.mainPage.model.Letter;
 import com.neighbors.tohero.domain.domain.mainPage.service.GetLetter;
+import jakarta.transaction.Transactional;
 import lombok.RequiredArgsConstructor;
 import org.springframework.stereotype.Service;
 
@@ -25,6 +27,7 @@ public class LetterService {
     private final CreateLetter createLetter;
     private final GetLetter getLetter;
     private final GetAddress getAddress;
+    private final UpdateLetter updateLetter;
 
     public BaseResponse<CreateLetterResponse> createLetter(final JwtUserDetails jwtUserDetail, final CreateLetterRequest createLetterRequest) {
 
@@ -68,6 +71,18 @@ public BaseResponse<GetMyLettersResponse> getMyLetters(long userId){
         );
     }
 
+    @Transactional
+    public BaseResponse<UpdateLetterPublicResponse> updateLetterPublic(long userId, UpdateLetterPublic updateLetterPublic){
+        updateLetter.updateLetterPublic(userId, updateLetterPublic.letterId(), updateLetterPublic.isPublic());
+
+        return new BaseResponse<>(
+                BaseResponseStatus.OK,
+                BaseResponseMessage.편지_공개_여부가_수정되었습니다.getMessage(),
+                UpdateLetterPublicResponse.of(updateLetterPublic.isPublic())
+        );
+    }
+
+
     private BaseResponse<CreateLetterResponse> createGuestLetter(final String nickname, final CreateLetterRequest createLetterRequest) {
         long createdLetterId = createLetter.createGuestLetter(
                 nickname,
diff --git a/src/main/java/com/neighbors/tohero/domain/domain/letter/service/UpdateLetter.java b/src/main/java/com/neighbors/tohero/domain/domain/letter/service/UpdateLetter.java
new file mode 100644
index 0000000..3e9fce1
--- /dev/null
+++ b/src/main/java/com/neighbors/tohero/domain/domain/letter/service/UpdateLetter.java
@@ -0,0 +1,16 @@
+package com.neighbors.tohero.domain.domain.letter.service;
+
+import com.neighbors.tohero.common.annotaion.DomainService;
+import com.neighbors.tohero.domain.query.LetterRepository;
+import lombok.RequiredArgsConstructor;
+
+@DomainService
+@RequiredArgsConstructor
+public class UpdateLetter {
+
+    private final LetterRepository letterRepository;
+
+    public void updateLetterPublic(long userId, long letterId, boolean isPublic){
+        letterRepository.updateLetter(repo -> repo.updateLetterPublic(userId, letterId, isPublic));
+    }
+}
diff --git a/src/main/java/com/neighbors/tohero/domain/query/LetterRepository.java b/src/main/java/com/neighbors/tohero/domain/query/LetterRepository.java
index af243b7..6508980 100644
--- a/src/main/java/com/neighbors/tohero/domain/query/LetterRepository.java
+++ b/src/main/java/com/neighbors/tohero/domain/query/LetterRepository.java
@@ -3,11 +3,10 @@
 import com.neighbors.tohero.domain.domain.mainPage.model.Letter;
 import com.neighbors.tohero.infrastructure.entity.LetterEntity;
 import com.neighbors.tohero.infrastructure.repository.LetterEntityRepository;
-import org.springframework.data.domain.Pageable;
-import org.springframework.stereotype.Repository;
 
 import java.util.List;
 import java.util.Optional;
+import java.util.function.Consumer;
 import java.util.function.Function;
 
 public interface LetterRepository {
@@ -16,4 +15,5 @@ public interface LetterRepository {
     Letter createLetter(Letter letter);
     void remainLetterWithoutUser(long userId);
     Letter getLetter(Function<LetterEntityRepository, Optional<LetterEntity>> function);
+    void updateLetter(Consumer<LetterEntityRepository> consumer);
 }
diff --git a/src/main/java/com/neighbors/tohero/infrastructure/query/impl/LetterRepositoryImpl.java b/src/main/java/com/neighbors/tohero/infrastructure/query/impl/LetterRepositoryImpl.java
index 2b9bd94..b4eacfd 100644
--- a/src/main/java/com/neighbors/tohero/infrastructure/query/impl/LetterRepositoryImpl.java
+++ b/src/main/java/com/neighbors/tohero/infrastructure/query/impl/LetterRepositoryImpl.java
@@ -15,6 +15,7 @@
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Optional;
+import java.util.function.Consumer;
 import java.util.function.Function;
 
 @Repository
@@ -69,4 +70,9 @@ public Letter getLetter(Function<LetterEntityRepository, Optional<LetterEntity>>
 
         return letterMapper.toDomain(letterEntity);
     }
+
+    @Override
+    public void updateLetter(Consumer<LetterEntityRepository> consumer) {
+        consumer.accept(letterEntityRepository);
+    }
 }
diff --git a/src/main/java/com/neighbors/tohero/infrastructure/repository/LetterEntityRepository.java b/src/main/java/com/neighbors/tohero/infrastructure/repository/LetterEntityRepository.java
index f13d20d..dba4d73 100644
--- a/src/main/java/com/neighbors/tohero/infrastructure/repository/LetterEntityRepository.java
+++ b/src/main/java/com/neighbors/tohero/infrastructure/repository/LetterEntityRepository.java
@@ -5,6 +5,7 @@
 import org.springframework.data.domain.Pageable;
 import org.springframework.data.domain.Slice;
 import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Modifying;
 import org.springframework.data.jpa.repository.Query;
 import org.springframework.stereotype.Repository;
 
@@ -25,4 +26,12 @@ public interface LetterEntityRepository extends JpaRepository<LetterEntity, Long
 
     @Query("SELECT le FROM LetterEntity le WHERE le.letterId = :letterId AND le.isPublic = true")
     Optional<LetterEntity> findByIdAndPublic(@Param("letterId") long letterId);
+
+    @Modifying
+    @Query("UPDATE LetterEntity le SET le.isPublic = :isPublic WHERE le.user.userId = :userId AND le.letterId = :letterId")
+    void updateLetterPublic(
+            @Param("userId") long userId,
+            @Param("letterId") long letterId,
+            @Param("isPublic") boolean isPublic
+    );
 }
diff --git a/src/main/java/com/neighbors/tohero/presentation/controller/LetterController.java b/src/main/java/com/neighbors/tohero/presentation/controller/LetterController.java
index 9bb192e..fa4a2ea 100644
--- a/src/main/java/com/neighbors/tohero/presentation/controller/LetterController.java
+++ b/src/main/java/com/neighbors/tohero/presentation/controller/LetterController.java
@@ -3,6 +3,7 @@
 import com.neighbors.tohero.application.baseResponse.BaseResponse;
 import com.neighbors.tohero.application.letter.dto.CreateLetterRequest;
 import com.neighbors.tohero.application.letter.dto.GetLetterDetailRequest;
+import com.neighbors.tohero.application.letter.dto.UpdateLetterPublic;
 import com.neighbors.tohero.application.letter.service.LetterService;
 import com.neighbors.tohero.common.jwt.JwtUserDetails;
 import io.swagger.v3.oas.annotations.Parameter;
@@ -40,4 +41,13 @@ public ResponseEntity<BaseResponse> getMyLetters(@Parameter(hidden = true) @Auth
         return ResponseEntity.ok()
                 .body(letterService.getMyLetters(jwtUserDetail.getUserId()));
     }
+
+    @PutMapping("")
+    public ResponseEntity<BaseResponse> updateLetterPublic(
+            @Parameter(hidden = true) @AuthenticationPrincipal JwtUserDetails jwtUserDetail,
+            @RequestBody @Validated UpdateLetterPublic updateLetterPublic
+    ){
+        return ResponseEntity.ok()
+                .body(letterService.updateLetterPublic(jwtUserDetail.getUserId(), updateLetterPublic));
+    }
 }