diff --git a/docs/rules/no-useless-undefined.md b/docs/rules/no-useless-undefined.md
index 5330339e3f..83cbc2eceb 100644
--- a/docs/rules/no-useless-undefined.md
+++ b/docs/rules/no-useless-undefined.md
@@ -69,7 +69,7 @@ function* foo() {
 ```
 
 ```js
-function foo(bar = undefined) {
+function foo(bar) {
 }
 ```