diff --git a/src/main/kotlin/kr/co/vividnext/sodalive/admin/chat/character/AdminChatCharacterController.kt b/src/main/kotlin/kr/co/vividnext/sodalive/admin/chat/character/AdminChatCharacterController.kt
index bea7f13..070719e 100644
--- a/src/main/kotlin/kr/co/vividnext/sodalive/admin/chat/character/AdminChatCharacterController.kt
+++ b/src/main/kotlin/kr/co/vividnext/sodalive/admin/chat/character/AdminChatCharacterController.kt
@@ -3,6 +3,7 @@ package kr.co.vividnext.sodalive.admin.chat.character
 import com.amazonaws.services.s3.model.ObjectMetadata
 import com.fasterxml.jackson.databind.ObjectMapper
 import kr.co.vividnext.sodalive.admin.chat.character.dto.ChatCharacterRegisterRequest
+import kr.co.vividnext.sodalive.admin.chat.character.dto.ChatCharacterUpdateRequest
 import kr.co.vividnext.sodalive.admin.chat.character.dto.ExternalApiResponse
 import kr.co.vividnext.sodalive.aws.s3.S3Uploader
 import kr.co.vividnext.sodalive.chat.character.service.ChatCharacterService
@@ -19,6 +20,7 @@ import org.springframework.retry.annotation.Backoff
 import org.springframework.retry.annotation.Retryable
 import org.springframework.security.access.prepost.PreAuthorize
 import org.springframework.web.bind.annotation.PostMapping
+import org.springframework.web.bind.annotation.PutMapping
 import org.springframework.web.bind.annotation.RequestMapping
 import org.springframework.web.bind.annotation.RequestPart
 import org.springframework.web.bind.annotation.RestController
@@ -144,4 +146,162 @@ class AdminChatCharacterController(
             throw SodaException("이미지 저장에 실패했습니다: ${e.message}")
         }
     }
+
+    /**
+     * 캐릭터 수정 API
+     * 1. JSON 문자열을 ChatCharacterUpdateRequest 객체로 변환
+     * 2. ChatCharacterUpdateRequest를 확인해서 변경한 데이터가 있는지 확인
+     * 3. 이미지 있는지 확인
+     * 4. 2, 3번 중 하나라도 해당 하면 계속 진행
+     * 5. 2, 3번에 데이터 없으면 throw SodaException('변경된 데이터가 없습니다.')
+     *
+     * @param image 캐릭터 이미지 (선택적)
+     * @param requestString ChatCharacterUpdateRequest 객체를 JSON 문자열로 변환한 값
+     * @return ApiResponse 객체
+     * @throws SodaException 변경된 데이터가 없거나 캐릭터를 찾을 수 없는 경우
+     */
+    @PutMapping("/update")
+    @Retryable(
+        value = [Exception::class],
+        maxAttempts = 3,
+        backoff = Backoff(delay = 1000)
+    )
+    fun updateCharacter(
+        @RequestPart(value = "image", required = false) image: MultipartFile?,
+        @RequestPart("request") requestString: String
+    ) = run {
+        // 1. JSON 문자열을 ChatCharacterUpdateRequest 객체로 변환
+        val objectMapper = ObjectMapper()
+        val request = objectMapper.readValue(requestString, ChatCharacterUpdateRequest::class.java)
+
+        // 2. ChatCharacterUpdateRequest를 확인해서 변경한 데이터가 있는지 확인
+        val hasChangedData = hasChanges(request)
+
+        // 3. 이미지 있는지 확인
+        val hasImage = image != null && !image.isEmpty
+
+        if (!hasChangedData && !hasImage) {
+            throw SodaException("변경된 데이터가 없습니다.")
+        }
+
+        // 변경된 데이터가 있으면 외부 API 호출
+        if (hasChangedData) {
+            val chatCharacter = service.findById(request.id)
+                ?: throw SodaException("해당 ID의 캐릭터를 찾을 수 없습니다: ${request.id}")
+            callExternalApiForUpdate(chatCharacter.characterUUID, request)
+        }
+
+        // 이미지 경로 변수 초기화
+        // 이미지가 있으면 이미지 저장
+        val imagePath = if (hasImage) {
+            saveImage(
+                characterId = request.id,
+                image = image!!
+            )
+        } else {
+            null
+        }
+
+        // 엔티티 수정
+        service.updateChatCharacterWithDetails(
+            imagePath = imagePath,
+            request = request
+        )
+
+        ApiResponse.ok(null)
+    }
+
+    /**
+     * 요청에 변경된 데이터가 있는지 확인
+     * id를 제외한 모든 필드가 null이면 변경된 데이터가 없는 것으로 판단
+     *
+     * @param request 수정 요청 데이터
+     * @return 변경된 데이터가 있으면 true, 없으면 false
+     */
+    private fun hasChanges(request: ChatCharacterUpdateRequest): Boolean {
+        return request.systemPrompt != null ||
+            request.description != null ||
+            request.age != null ||
+            request.gender != null ||
+            request.mbti != null ||
+            request.speechPattern != null ||
+            request.speechStyle != null ||
+            request.appearance != null ||
+            request.isActive != null ||
+            request.tags != null ||
+            request.hobbies != null ||
+            request.values != null ||
+            request.goals != null ||
+            request.relationships != null ||
+            request.personalities != null ||
+            request.backgrounds != null ||
+            request.memories != null ||
+            request.name != null
+    }
+
+    /**
+     * 외부 API 호출 - 수정 API
+     * 변경된 데이터만 요청에 포함
+     *
+     * @param characterUUID 캐릭터 UUID
+     * @param request 수정 요청 데이터
+     */
+    private fun callExternalApiForUpdate(characterUUID: String, request: ChatCharacterUpdateRequest) {
+        try {
+            val factory = SimpleClientHttpRequestFactory()
+            factory.setConnectTimeout(20000) // 20초
+            factory.setReadTimeout(20000) // 20초
+
+            val restTemplate = RestTemplate(factory)
+
+            val headers = HttpHeaders()
+            headers.set("x-api-key", apiKey)
+            headers.contentType = MediaType.APPLICATION_JSON
+
+            // 변경된 데이터만 포함하는 맵 생성
+            val updateData = mutableMapOf<String, Any>()
+
+            if (request.isActive != null && !request.isActive) {
+                updateData["name"] = "inactive_${request.name}"
+            } else {
+                request.name?.let { updateData["name"] = it }
+                request.systemPrompt?.let { updateData["systemPrompt"] = it }
+                request.description?.let { updateData["description"] = it }
+                request.age?.let { updateData["age"] = it }
+                request.gender?.let { updateData["gender"] = it }
+                request.mbti?.let { updateData["mbti"] = it }
+                request.speechPattern?.let { updateData["speechPattern"] = it }
+                request.speechStyle?.let { updateData["speechStyle"] = it }
+                request.appearance?.let { updateData["appearance"] = it }
+                request.tags?.let { updateData["tags"] = it }
+                request.hobbies?.let { updateData["hobbies"] = it }
+                request.values?.let { updateData["values"] = it }
+                request.goals?.let { updateData["goals"] = it }
+                request.relationships?.let { updateData["relationships"] = it }
+                request.personalities?.let { updateData["personalities"] = it }
+                request.backgrounds?.let { updateData["backgrounds"] = it }
+                request.memories?.let { updateData["memories"] = it }
+            }
+
+            val httpEntity = HttpEntity(updateData, headers)
+
+            val response = restTemplate.exchange(
+                "$apiUrl/api/characters/$characterUUID",
+                HttpMethod.PUT,
+                httpEntity,
+                String::class.java
+            )
+
+            // 응답 파싱
+            val objectMapper = ObjectMapper()
+            val apiResponse = objectMapper.readValue(response.body, ExternalApiResponse::class.java)
+
+            // success가 false이면 throw
+            if (!apiResponse.success) {
+                throw SodaException(apiResponse.message ?: "수정에 실패했습니다. 다시 시도해 주세요.")
+            }
+        } catch (_: Exception) {
+            throw SodaException("수정에 실패했습니다. 다시 시도해 주세요.")
+        }
+    }
 }
diff --git a/src/main/kotlin/kr/co/vividnext/sodalive/admin/chat/character/dto/ChatCharacterDto.kt b/src/main/kotlin/kr/co/vividnext/sodalive/admin/chat/character/dto/ChatCharacterDto.kt
index 299bdfd..94cf606 100644
--- a/src/main/kotlin/kr/co/vividnext/sodalive/admin/chat/character/dto/ChatCharacterDto.kt
+++ b/src/main/kotlin/kr/co/vividnext/sodalive/admin/chat/character/dto/ChatCharacterDto.kt
@@ -46,3 +46,25 @@ data class ExternalApiResponse(
 data class ExternalApiData(
     val id: String
 )
+
+data class ChatCharacterUpdateRequest(
+    val id: Long,
+    val name: String? = null,
+    val systemPrompt: String? = null,
+    val description: String? = null,
+    val age: String? = null,
+    val gender: String? = null,
+    val mbti: String? = null,
+    val speechPattern: String? = null,
+    val speechStyle: String? = null,
+    val appearance: String? = null,
+    val isActive: Boolean? = null,
+    val tags: List<String>? = null,
+    val hobbies: List<String>? = null,
+    val values: List<String>? = null,
+    val goals: List<String>? = null,
+    val relationships: List<String>? = null,
+    val personalities: List<ChatCharacterPersonalityRequest>? = null,
+    val backgrounds: List<ChatCharacterBackgroundRequest>? = null,
+    val memories: List<ChatCharacterMemoryRequest>? = null
+)
diff --git a/src/main/kotlin/kr/co/vividnext/sodalive/chat/character/ChatCharacter.kt b/src/main/kotlin/kr/co/vividnext/sodalive/chat/character/ChatCharacter.kt
index 42fd8f0..a5a3e86 100644
--- a/src/main/kotlin/kr/co/vividnext/sodalive/chat/character/ChatCharacter.kt
+++ b/src/main/kotlin/kr/co/vividnext/sodalive/chat/character/ChatCharacter.kt
@@ -12,37 +12,37 @@ class ChatCharacter(
     val characterUUID: String,
 
     // 캐릭터 이름 (API 키 내에서 유일해야 함)
-    val name: String,
+    var name: String,
 
     // 캐릭터 설명
     @Column(columnDefinition = "TEXT", nullable = false)
-    val description: String,
+    var description: String,
 
     // AI 시스템 프롬프트
     @Column(columnDefinition = "TEXT", nullable = false)
-    val systemPrompt: String,
+    var systemPrompt: String,
 
     // 나이
-    val age: Int? = null,
+    var age: Int? = null,
 
     // 성별
-    val gender: String? = null,
+    var gender: String? = null,
 
     // mbti
-    val mbti: String? = null,
+    var mbti: String? = null,
 
     // 말투 패턴 설명
     @Column(columnDefinition = "TEXT")
-    val speechPattern: String? = null,
+    var speechPattern: String? = null,
 
     // 대화 스타일
-    val speechStyle: String? = null,
+    var speechStyle: String? = null,
 
     // 외모 설명
     @Column(columnDefinition = "TEXT")
-    val appearance: String? = null,
+    var appearance: String? = null,
 
-    val isActive: Boolean = true
+    var isActive: Boolean = true
 ) : BaseEntity() {
     var imagePath: String? = null
 
diff --git a/src/main/kotlin/kr/co/vividnext/sodalive/chat/character/service/ChatCharacterService.kt b/src/main/kotlin/kr/co/vividnext/sodalive/chat/character/service/ChatCharacterService.kt
index 3ffad40..af72b69 100644
--- a/src/main/kotlin/kr/co/vividnext/sodalive/chat/character/service/ChatCharacterService.kt
+++ b/src/main/kotlin/kr/co/vividnext/sodalive/chat/character/service/ChatCharacterService.kt
@@ -1,5 +1,6 @@
 package kr.co.vividnext.sodalive.chat.character.service
 
+import kr.co.vividnext.sodalive.admin.chat.character.dto.ChatCharacterUpdateRequest
 import kr.co.vividnext.sodalive.chat.character.ChatCharacter
 import kr.co.vividnext.sodalive.chat.character.ChatCharacterGoal
 import kr.co.vividnext.sodalive.chat.character.ChatCharacterHobby
@@ -134,6 +135,14 @@ class ChatCharacterService(
         return chatCharacterRepository.findAll()
     }
 
+    /**
+     * ID로 캐릭터 조회
+     */
+    @Transactional(readOnly = true)
+    fun findById(id: Long): ChatCharacter? {
+        return chatCharacterRepository.findById(id).orElse(null)
+    }
+
     /**
      * 캐릭터 생성 및 관련 엔티티 연결
      */
@@ -260,4 +269,100 @@ class ChatCharacterService(
 
         return saveChatCharacter(chatCharacter)
     }
+
+    /**
+     * 캐릭터 수정 시 기본 정보와 함께 추가 정보도 설정
+     * 이름은 변경할 수 없으므로 이름은 변경하지 않음
+     * 변경된 데이터만 업데이트
+     *
+     * @param imagePath 이미지 경로 (null이면 이미지 변경 없음)
+     * @param request 수정 요청 데이터 (id를 제외한 모든 필드는 null 가능)
+     * @return 수정된 ChatCharacter 객체
+     * @throws SodaException 캐릭터를 찾을 수 없는 경우
+     */
+    @Transactional
+    fun updateChatCharacterWithDetails(
+        imagePath: String? = null,
+        request: ChatCharacterUpdateRequest
+    ): ChatCharacter {
+        // 캐릭터 조회
+        val chatCharacter = findById(request.id)
+            ?: throw kr.co.vividnext.sodalive.common.SodaException("해당 ID의 캐릭터를 찾을 수 없습니다: ${request.id}")
+
+        // isActive가 false이면 isActive = false, name = "inactive_$name"으로 변경하고 나머지는 반영하지 않는다.
+        if (request.isActive != null && !request.isActive) {
+            chatCharacter.isActive = false
+            chatCharacter.name = "inactive_${chatCharacter.name}"
+
+            return saveChatCharacter(chatCharacter)
+        }
+
+        // 이미지 경로가 있으면 설정
+        if (imagePath != null) {
+            chatCharacter.imagePath = imagePath
+        }
+
+        // 기본 필드 업데이트 - 변경된 데이터만 업데이트
+        request.name?.let { chatCharacter.name = it }
+        request.systemPrompt?.let { chatCharacter.systemPrompt = it }
+        request.description?.let { chatCharacter.description = it }
+        request.age?.toIntOrNull()?.let { chatCharacter.age = it }
+        request.gender?.let { chatCharacter.gender = it }
+        request.mbti?.let { chatCharacter.mbti = it }
+        request.speechPattern?.let { chatCharacter.speechPattern = it }
+        request.speechStyle?.let { chatCharacter.speechStyle = it }
+        request.appearance?.let { chatCharacter.appearance = it }
+
+        // request에서 변경된 데이터만 업데이트
+        if (request.tags != null) {
+            chatCharacter.tagMappings.clear()
+            addTagsToCharacter(chatCharacter, request.tags)
+        }
+
+        if (request.values != null) {
+            chatCharacter.valueMappings.clear()
+            addValuesToCharacter(chatCharacter, request.values)
+        }
+
+        if (request.hobbies != null) {
+            chatCharacter.hobbyMappings.clear()
+            addHobbiesToCharacter(chatCharacter, request.hobbies)
+        }
+
+        if (request.goals != null) {
+            chatCharacter.goalMappings.clear()
+            addGoalsToCharacter(chatCharacter, request.goals)
+        }
+
+        // 추가 정보 설정 - 변경된 데이터만 업데이트
+        if (request.memories != null) {
+            chatCharacter.memories.clear()
+            request.memories.forEach { memory ->
+                chatCharacter.addMemory(memory.title, memory.content, memory.emotion)
+            }
+        }
+
+        if (request.personalities != null) {
+            chatCharacter.personalities.clear()
+            request.personalities.forEach { personality ->
+                chatCharacter.addPersonality(personality.trait, personality.description)
+            }
+        }
+
+        if (request.backgrounds != null) {
+            chatCharacter.backgrounds.clear()
+            request.backgrounds.forEach { background ->
+                chatCharacter.addBackground(background.topic, background.description)
+            }
+        }
+
+        if (request.relationships != null) {
+            chatCharacter.relationships.clear()
+            request.relationships.forEach { relationship ->
+                chatCharacter.addRelationship(relationship)
+            }
+        }
+
+        return saveChatCharacter(chatCharacter)
+    }
 }