diff --git a/src/main/resources/templates/views/apps/mypage/apiKeyModifyStep2.html b/src/main/resources/templates/views/apps/mypage/apiKeyModifyStep2.html
index 12aa295..a1b0a0a 100644
--- a/src/main/resources/templates/views/apps/mypage/apiKeyModifyStep2.html
+++ b/src/main/resources/templates/views/apps/mypage/apiKeyModifyStep2.html
@@ -711,13 +711,11 @@
 
       // Form validation
       form.addEventListener('submit', function(e) {
-        // Allow submission even without selected APIs (user might want to remove all)
-        // But show confirmation
+        // API 선택 필수 검증
         if (selectedApis.size === 0) {
-          if (!confirm('API를 선택하지 않으셨습니다. 계속하시겠습니까?')) {
-            e.preventDefault();
-            return false;
-          }
+          e.preventDefault();
+          customPopups.showAlert('최소 1개 이상의 API를 선택해주세요.');
+          return false;
         }
       });
 
diff --git a/src/main/resources/templates/views/apps/mypage/apiKeyRegisterStep2.html b/src/main/resources/templates/views/apps/mypage/apiKeyRegisterStep2.html
index c6cba0d..eddbc67 100644
--- a/src/main/resources/templates/views/apps/mypage/apiKeyRegisterStep2.html
+++ b/src/main/resources/templates/views/apps/mypage/apiKeyRegisterStep2.html
@@ -657,10 +657,7 @@
       form.addEventListener('submit', function(e) {
         if (selectedApis.size === 0) {
           e.preventDefault();
-          if (confirm('API를 선택하지 않으셨습니다. 나중에 추가하시겠습니까?')) {
-            // Allow form submission without selected APIs
-            form.submit();
-          }
+          customPopups.showAlert('최소 1개 이상의 API를 선택해주세요.');
           return false;
         }