diff --git a/lib/client.js b/lib/client.js
index 853a6846..fa1965c2 100644
--- a/lib/client.js
+++ b/lib/client.js
@@ -149,7 +149,7 @@ var Util, DOM, CloudFunc, CloudCmd;
         Util.ifExec(document.body.scrollIntoViewIfNeeded, lCallBack, lFunc);
         
         DOM.Events.add(['unload', 'beforeunload'], function (pEvent) {
-                var lRet, lIsBind = Key.isBind();
+                var lRet, lIsBind = Key && Key.isBind();
                 
                 if(!lIsBind) {
                     DOM.preventDefault(pEvent);