diff --git a/library/think/Model.php b/library/think/Model.php
index df3692ed..fde0c318 100644
--- a/library/think/Model.php
+++ b/library/think/Model.php
@@ -300,7 +300,7 @@ abstract class Model implements \JsonSerializable, \ArrayAccess
         }
 
         // 标记字段更改
-        if (!isset($this->data[$name]) || ($this->data[$name] != $value && !in_array($name, $this->change))) {
+        if (!isset($this->data[$name]) || (0 !== strcmp($this->data[$name], $value) && !in_array($name, $this->change))) {
             $this->change[] = $name;
         }
         // 设置数据对象属性