diff --git a/graphic/graphic_2d/native_window/external_window.h b/graphic/graphic_2d/native_window/external_window.h
index 54ae4efe5b71ba9d00ec417efc9601c13f73b06d..fac4e78d357586ff5f45901eb6b531ab31d60fa1 100644
--- a/graphic/graphic_2d/native_window/external_window.h
+++ b/graphic/graphic_2d/native_window/external_window.h
@@ -236,6 +236,7 @@ typedef enum NativeWindowOperation {
     SET_APP_FRAMEWORK_TYPE,
     /**
      * get app framework type,
+     * after this operation, caller needs to delete[] frameworkType to free memory.
      * variable parameter in function is
      * [out] char** frameworkType.
      * @since 12