diff --git a/src/main/kotlin/kr/co/vividnext/sodalive/admin/chat/original/service/AdminOriginalWorkService.kt b/src/main/kotlin/kr/co/vividnext/sodalive/admin/chat/original/service/AdminOriginalWorkService.kt
index 288ddf5..57dcce7 100644
--- a/src/main/kotlin/kr/co/vividnext/sodalive/admin/chat/original/service/AdminOriginalWorkService.kt
+++ b/src/main/kotlin/kr/co/vividnext/sodalive/admin/chat/original/service/AdminOriginalWorkService.kt
@@ -145,11 +145,17 @@ class AdminOriginalWorkService(
     /** 단일 캐릭터를 지정 원작에 배정 */
     @Transactional
     fun assignOneCharacter(originalWorkId: Long, characterId: Long) {
-        val ow = originalWorkRepository.findByIdAndIsDeletedFalse(originalWorkId)
-            .orElseThrow { SodaException("해당 원작을 찾을 수 없습니다") }
         val character = chatCharacterRepository.findById(characterId)
             .orElseThrow { SodaException("해당 캐릭터를 찾을 수 없습니다") }
-        character.originalWork = ow
+
+        if (characterId == 0L) {
+            character.originalWork = null
+        } else {
+            val ow = originalWorkRepository.findByIdAndIsDeletedFalse(originalWorkId)
+                .orElseThrow { SodaException("해당 원작을 찾을 수 없습니다") }
+            character.originalWork = ow
+        }
+
         chatCharacterRepository.save(character)
     }
 }