diff --git a/backend/src/main/java/com/twtw/backend/domain/group/service/GroupService.java b/backend/src/main/java/com/twtw/backend/domain/group/service/GroupService.java
index 291733c1..904c8f26 100644
--- a/backend/src/main/java/com/twtw/backend/domain/group/service/GroupService.java
+++ b/backend/src/main/java/com/twtw/backend/domain/group/service/GroupService.java
@@ -45,7 +45,7 @@ public void joinGroup(UUID groupId) {
         Group group =
                 groupRepository.findById(groupId).orElseThrow(EntityNotFoundException::new);
 
-        GroupMember groupMember = groupMapper.connectGroupMember(group, member);
+        groupMapper.connectGroupMember(group, member);
     }
 
     public void removeGroup(UUID groupId) {