diff --git a/src/base/pane.js b/src/base/pane.js
index cc7e9b61b8..6bd53d848c 100644
--- a/src/base/pane.js
+++ b/src/base/pane.js
@@ -86,6 +86,7 @@ BI.Pane = BI.inherit(BI.Widget, {
                 items: this._getLoadingTipItems(this._loading)
             });
         }
+        self.fireEvent(BI.Pane.EVENT_LOADING);
         this.element.addClass("loading-status");
     },
 
@@ -143,4 +144,5 @@ BI.Pane = BI.inherit(BI.Widget, {
 
     }
 });
-BI.Pane.EVENT_LOADED = "EVENT_LOADED";
\ No newline at end of file
+BI.Pane.EVENT_LOADED = "EVENT_LOADED";
+BI.Pane.EVENT_LOADING = "EVENT_LOADING";
\ No newline at end of file
diff --git a/typescript/base/pane.ts b/typescript/base/pane.ts
index 4a618e5b51..f2d448978f 100644
--- a/typescript/base/pane.ts
+++ b/typescript/base/pane.ts
@@ -2,6 +2,7 @@ import { Widget } from "../core/widget";
 
 export declare class Pane extends Widget {
     static EVENT_LOADED: string;
+    static EVENT_LOADING: string;
 
     _assertTip(..._args: any[]): void;
     loading(): void;