diff --git a/docs/demo/index.js b/docs/demo/index.js
index 4299e3013..7c6951e62 100644
--- a/docs/demo/index.js
+++ b/docs/demo/index.js
@@ -7,3 +7,6 @@ dayjs('2018-08-08').format()
 
 // format
 dayjs().format('YYYY-MM-DD')
+
+// locale
+dayjs().locale('zh-cn').format()