diff --git a/zh-cn/application-dev/reference/apis/js-apis-distributedKVStore.md b/zh-cn/application-dev/reference/apis/js-apis-distributedKVStore.md
index 7eed43c95614580c4b2832cc93d0f80cf481f4a9..d81db309a30d828e3b33183bcc7aca094a4cc080 100644
--- a/zh-cn/application-dev/reference/apis/js-apis-distributedKVStore.md
+++ b/zh-cn/application-dev/reference/apis/js-apis-distributedKVStore.md
@@ -3867,7 +3867,7 @@ backup(file:string, callback: AsyncCallback<void>):void
 ```js
 let file = "BK001";
 try {
-    kvStore.backup(file, function(err) => {
+    kvStore.backup(file, (err) => {
         if (err) {
             console.error(`Failed to backup.code is ${err.code},message is ${err.message} `);
         } else {