diff --git a/runtime/ftplugin/gomod.vim b/runtime/ftplugin/gomod.vim
index 0d5d9ba..554c948 100644
--- a/runtime/ftplugin/gomod.vim
+++ b/runtime/ftplugin/gomod.vim
@@ -2,13 +2,15 @@
 " Language:    go module file
 " Maintainer:  YU YUK KUEN <yukkuen.yu719@gmail.com>
 " Last Change: 2024-06-21
+" 2024 Jul 16 by Vim Project (noexpandtab)
 
 if exists('b:did_ftplugin')
   finish
 endif
 let b:did_ftplugin = 1
 
+setlocal noexpandtab
 setlocal formatoptions-=t formatoptions-=c
 setlocal commentstring=//\ %s
 
-let b:undo_ftplugin = 'setl fo< cms<'
+let b:undo_ftplugin = 'setl et< fo< cms<'