diff --git a/README.md b/README.md
index 88953c1..bb8b81e 100644
--- a/README.md
+++ b/README.md
@@ -41,7 +41,7 @@ go get -v github.com/codeskyblue/gohttpserver
 Listen port 8000 on all interface, and enable upload
 
 ```
-./gohttpserver --addr :8000 --upload
+./gohttpserver -r ./ --addr :8000 --upload
 ```
 
 ### ipa plist proxy
diff --git a/main.go b/main.go
index 8105246..b02fa5b 100644
--- a/main.go
+++ b/main.go
@@ -31,6 +31,7 @@ var (
 
 func parseFlags() {
 	kingpin.HelpFlag.Short('h')
+	kingpin.Flag("root", "root directory").Short('r').Default("./").StringVar(&gcfg.Root)
 	kingpin.Flag("addr", "listen address").Short('a').Default(":8000").StringVar(&gcfg.Addr)
 	kingpin.Flag("cert", "tls cert.pem path").StringVar(&gcfg.Cert)
 	kingpin.Flag("key", "tls key.pem path").StringVar(&gcfg.Key)
@@ -47,7 +48,7 @@ func parseFlags() {
 func main() {
 	parseFlags()
 
-	ss := NewHTTPStaticServer("./")
+	ss := NewHTTPStaticServer(gcfg.Root)
 	ss.Theme = gcfg.Theme
 
 	log.Println(gcfg.PlistProxy)