diff --git a/adm/dbupgrade.php b/adm/dbupgrade.php
index 7ac478d40..aaeb4e60c 100644
--- a/adm/dbupgrade.php
+++ b/adm/dbupgrade.php
@@ -207,6 +207,18 @@ if (defined('G5_USE_SHOP') && G5_USE_SHOP) {
     }
 }
 
+// auth.au_menu 컬럼 크기 조정
+$sql = " SHOW COLUMNS FROM `{$g5['auth_table']}` LIKE 'au_menu' ";
+$row = sql_fetch($sql);
+if (
+    stripos($row['Type'], 'varchar') !== false
+    && (int) preg_replace('/[^0-9]/', '', $row['Type']) <= 50
+) {
+    sql_query(" ALTER TABLE `{$g5['auth_table']}` CHANGE `au_menu` `au_menu` VARCHAR(50) NOT NULL; ", true);
+
+    $is_check = true;
+}
+
 $is_check = run_replace('admin_dbupgrade', $is_check);
 
 $db_upgrade_msg = $is_check ? 'DB 업그레이드가 완료되었습니다.' : '더 이상 업그레이드 할 내용이 없습니다.<br>현재 DB 업그레이드가 완료된 상태입니다.';
diff --git a/install/gnuboard5.sql b/install/gnuboard5.sql
index 749e9f796..150050cf0 100644
--- a/install/gnuboard5.sql
+++ b/install/gnuboard5.sql
@@ -7,7 +7,7 @@
 DROP TABLE IF EXISTS `g5_auth`;
 CREATE TABLE IF NOT EXISTS `g5_auth` (
   `mb_id` varchar(20) NOT NULL default '',
-  `au_menu` varchar(20) NOT NULL default '',
+  `au_menu` varchar(50) NOT NULL default '',
   `au_auth` set('r','w','d') NOT NULL default '',
   PRIMARY KEY  (`mb_id`,`au_menu`)
 ) ENGINE=MyISAM DEFAULT CHARSET=utf8;