diff --git a/interfaces/kits/napi/window_runtime/window_napi/js_window.cpp b/interfaces/kits/napi/window_runtime/window_napi/js_window.cpp
index bf783a9d9b06e44b8b1f922dacda91ade1cbfa1e..97919ea54c299e5558c03d5b6f3ae7d7f173cf57 100644
--- a/interfaces/kits/napi/window_runtime/window_napi/js_window.cpp
+++ b/interfaces/kits/napi/window_runtime/window_napi/js_window.cpp
@@ -8987,6 +8987,10 @@ napi_value JsWindow::OnSetRelativePositionToParentWindowEnabled(napi_env env, na
         TLOGE(WmsLogTag::WMS_SUB, "Failed to convert parameter to anchor");
         return NapiThrowError(env, WmErrorCode::WM_ERROR_INVALID_PARAM);
     }
+    if (anchor > WindowAnchor::BOTTOM_END || anchor < WindowAnchor::TOP_START) {
+        TLOGE(WmsLogTag::WMS_SUB, "UnKnown window anchor");
+        return NapiThrowError(env, WmErrorCode::WM_ERROR_ILLEGAL_PARAM);
+    }
     int32_t offsetX = 0;
     if (argc > INDEX_TWO && !ConvertFromJsValue(env, argv[INDEX_TWO], offsetX)) {
         TLOGE(WmsLogTag::WMS_SUB, "Failed to convert parameter to offsetX");