diff --git a/src/pages/Chat/ChatRoom.tsx b/src/pages/Chat/ChatRoom.tsx
index 93fa7517..a2e36473 100644
--- a/src/pages/Chat/ChatRoom.tsx
+++ b/src/pages/Chat/ChatRoom.tsx
@@ -121,9 +121,12 @@ function ChatRoom() {
                       </div>
                     </div>
 
-                    <span className="mb-1 shrink-0 self-end text-xs text-indigo-300">
-                      {formatTime(message.createdAt)}
-                    </span>
+                    <div className="flex shrink-0 flex-col items-start gap-0.5 self-end">
+                      {message.unreadCount > 0 && (
+                        <span className="text-[10px] font-medium text-[#4B9FE1]">{message.unreadCount}</span>
+                      )}
+                      <span className="text-[10px] text-indigo-300">{formatTime(message.createdAt)}</span>
+                    </div>
                   </div>
                 )}
 
@@ -134,9 +137,12 @@ function ChatRoom() {
                       {message.content}
                     </div>
 
-                    <span className="mb-1 shrink-0 self-end text-xs text-indigo-300">
-                      {formatTime(message.createdAt)}
-                    </span>
+                    <div className="flex shrink-0 flex-col items-end self-end">
+                      {message.unreadCount > 0 && (
+                        <span className="text-[10px] font-medium text-[#4B9FE1]">{message.unreadCount}</span>
+                      )}
+                      <span className="text-[10px] text-indigo-300">{formatTime(message.createdAt)}</span>
+                    </div>
                   </div>
                 )}
               </div>
diff --git a/src/pages/Club/Application/hooks/useApplyToClub.ts b/src/pages/Club/Application/hooks/useApplyToClub.ts
index db3b9986..8dc6745e 100644
--- a/src/pages/Club/Application/hooks/useApplyToClub.ts
+++ b/src/pages/Club/Application/hooks/useApplyToClub.ts
@@ -8,7 +8,7 @@ const useApplyToClub = (clubId: number) => {
   const navigate = useNavigate();
   const queryClient = useQueryClient();
 
-  const { mutateAsync: applyToClub } = useMutation({
+  const { mutateAsync: applyToClub, isPending } = useMutation({
     mutationKey: ['applyToClub', clubId],
     mutationFn: (body: ClubApplyRequest) => applyClub(clubId, body),
     onSuccess: () => {
@@ -17,7 +17,7 @@ const useApplyToClub = (clubId: number) => {
     },
   });
 
-  return { applyToClub };
+  return { applyToClub, isPending };
 };
 
 export default useApplyToClub;
diff --git a/src/pages/Club/Application/hooks/useClubApply.ts b/src/pages/Club/Application/hooks/useClubApply.ts
index 10167e3c..b2b0ac9a 100644
--- a/src/pages/Club/Application/hooks/useClubApply.ts
+++ b/src/pages/Club/Application/hooks/useClubApply.ts
@@ -22,13 +22,13 @@ const useClubApply = (clubId: number) => {
   const hasFeeData = clubFee.amount !== null && clubFee.accountNumber !== null;
   const isFeeRequired = recruitment.isFeeRequired && hasFeeData;
 
-  const { applyToClub } = useApplyToClub(clubId);
+  const { applyToClub, isPending } = useApplyToClub(clubId);
 
   const applyDirectly = () => applyToClub({ answers: [] });
 
   const hasQuestions = clubQuestions && clubQuestions.questions.length > 0;
 
-  return { clubQuestions, applyToClub, applyDirectly, hasQuestions, isFeeRequired };
+  return { clubQuestions, applyToClub, applyDirectly, hasQuestions, isFeeRequired, isPending };
 };
 
 export default useClubApply;
diff --git a/src/pages/Club/Application/index.tsx b/src/pages/Club/Application/index.tsx
index 1d453f48..a6a9211b 100644
--- a/src/pages/Club/Application/index.tsx
+++ b/src/pages/Club/Application/index.tsx
@@ -8,7 +8,7 @@ import useClubApply from './hooks/useClubApply';
 function ApplicationPage() {
   const { clubId } = useParams();
   const navigate = useNavigate();
-  const { clubQuestions, applyToClub, isFeeRequired } = useClubApply(Number(clubId));
+  const { clubQuestions, applyToClub, isFeeRequired, isPending } = useClubApply(Number(clubId));
   const { answers: storedAnswers, clubId: storedClubId } = useClubApplicationStore();
   const setApplication = useClubApplicationStore((s) => s.setApplication);
   const [answers, setAnswers] = useState<Record<number, string>>(() =>
@@ -80,7 +80,8 @@ function ApplicationPage() {
             <button
               type="button"
               onClick={handleConfirm}
-              className="bg-primary text-h3 w-full rounded-lg py-3.5 text-center text-white"
+              disabled={isPending}
+              className="bg-primary text-h3 w-full rounded-lg py-3.5 text-center text-white disabled:opacity-50"
             >
               제출하기
             </button>
diff --git a/src/pages/Club/ClubDetail/components/ClubRecruitment.tsx b/src/pages/Club/ClubDetail/components/ClubRecruitment.tsx
index af0f715e..8d4604b0 100644
--- a/src/pages/Club/ClubDetail/components/ClubRecruitment.tsx
+++ b/src/pages/Club/ClubDetail/components/ClubRecruitment.tsx
@@ -14,7 +14,7 @@ interface ClubRecruitProps {
 function ClubRecruitment({ clubId, isMember }: ClubRecruitProps) {
   const navigate = useNavigate();
   const { data: clubRecruitment } = useGetClubRecruitment(clubId);
-  const { hasQuestions, applyDirectly, isFeeRequired } = useClubApply(clubId);
+  const { hasQuestions, applyDirectly, isFeeRequired, isPending } = useClubApply(clubId);
   const { value: isConfirmOpen, setTrue: openConfirm, setFalse: closeConfirm } = useBooleanState();
 
   const setApplication = useClubApplicationStore((s) => s.setApplication);
@@ -95,7 +95,8 @@ function ClubRecruitment({ clubId, isMember }: ClubRecruitProps) {
             <button
               type="button"
               onClick={handleApply}
-              className="bg-primary text-h3 w-full rounded-lg py-3.5 text-center text-white"
+              disabled={isPending}
+              className="bg-primary text-h3 w-full rounded-lg py-3.5 text-center text-white disabled:opacity-50"
             >
               지원하기
             </button>