diff --git a/app/admin/common.php b/app/admin/common.php
index b8a612cb..878fc5c1 100644
--- a/app/admin/common.php
+++ b/app/admin/common.php
@@ -15,11 +15,12 @@ if (!function_exists('array_to_tree')) {
         $ret = [];
         foreach ($data as $item) {
             if ($item[$with] == $pid) {
+                $lv = $level;
                 if ($level !== false) {
                     $item['level'] = $level;
-                    $level         = $level + 1;
+                    $lv            = $level + 1;
                 }
-                $children = array_to_tree($data, $item['id'], $with, $level);
+                $children = array_to_tree($data, $item['id'], $with, $lv);
                 if ($children) {
                     $item['children'] = $children;
                 }