diff --git a/zh-cn/application-dev/reference/apis/js-apis-plainarray.md b/zh-cn/application-dev/reference/apis/js-apis-plainarray.md
index 2a96f5917a46f4c7d3bc2d868ca1b70b8893ff1f..b6a81a607cb3aeacbd8b970e5349fd410a72a754 100644
--- a/zh-cn/application-dev/reference/apis/js-apis-plainarray.md
+++ b/zh-cn/application-dev/reference/apis/js-apis-plainarray.md
@@ -153,7 +153,7 @@ getIndexOfKey(key: number): number
 let plainArray = new PlainArray();
 plainArray.add(1, "sddfhf");
 plainArray.add(2, "sffdfhf");
-let result = plainArray.getIndexOfKey("sdfs");
+let result = plainArray.getIndexOfKey(2);
 ```