diff --git a/library/think/Model.php b/library/think/Model.php
index 391f78b6..d2f7b640 100644
--- a/library/think/Model.php
+++ b/library/think/Model.php
@@ -1074,7 +1074,7 @@ abstract class Model implements \JsonSerializable, \ArrayAccess
 
             foreach ((array) $pk as $key) {
                 if (isset($data[$key])) {
-                    $array[] = [$key, '=', $data[$key]];
+                    $array[$key] = $data[$key];
                     unset($data[$key]);
                 }
             }