diff --git a/library/think/db/Query.php b/library/think/db/Query.php
index 70b8279d..041e5e6f 100644
--- a/library/think/db/Query.php
+++ b/library/think/db/Query.php
@@ -708,6 +708,7 @@ class Query
         // 传入的表名为数组
         if (is_array($join)) {
             $table = $join;
+            $alias = array_shift($join);
         } else {
             $join = trim($join);
             if (false !== strpos($join, '(')) {