diff --git a/youtube/youtube-dl/README.md b/youtube/youtube-dl/README.md
index 46f2681..8257251 100644
--- a/youtube/youtube-dl/README.md
+++ b/youtube/youtube-dl/README.md
@@ -8,7 +8,7 @@ youtube-dl
 
 ```
 # create a alias
-$ alias yt='docker run --rm -v `pwd`:/data vimagick/youtube-dl'
+$ alias yt='docker run --rm -u $(id -u):$(id -g) -v `pwd`:/data vimagick/youtube-dl'
 
 # list all formats
 $ yt -F nVjsGKrE6E8