diff --git a/projects/ucap-webmessenger-app/src/app/store/messenger/event/effects.ts b/projects/ucap-webmessenger-app/src/app/store/messenger/event/effects.ts
index e2455f2f..a98800ea 100644
--- a/projects/ucap-webmessenger-app/src/app/store/messenger/event/effects.ts
+++ b/projects/ucap-webmessenger-app/src/app/store/messenger/event/effects.ts
@@ -179,7 +179,11 @@ export class Effects {
         // map(([action, roomInfo]) => ([action.noti, roomInfo])),
         tap(([action, roomInfo, loginRes]) => {
           // 현재 오픈된 방에 대한 read noti/res 가 유입될 경우 roomUserList 의 lastReadSeq 를 갱신한다.
-          if (roomInfo.roomSeq === action.roomSeq) {
+          if (
+            !!roomInfo &&
+            !!roomInfo.roomSeq &&
+            roomInfo.roomSeq === action.roomSeq
+          ) {
             this.store.dispatch(RoomStore.updateRoomUserLastReadSeq(action));
           }