diff --git a/musicutil/__main__.py b/musicutil/__main__.py
index 6638d7f..99ae32c 100644
--- a/musicutil/__main__.py
+++ b/musicutil/__main__.py
@@ -27,6 +27,8 @@ def main():
         TranscodeCommand(get_transcode_args(args)).run()
     elif args.subparser_name == "genhtml":
         GenHTMLCommand(get_genhtml_args(args)).run()
+    else:
+        parser.print_help()
 
 if __name__ == "__main__":
     main()
\ No newline at end of file