diff --git a/library/think/Model.php b/library/think/Model.php
index eeee9b36..e03970e1 100644
--- a/library/think/Model.php
+++ b/library/think/Model.php
@@ -952,6 +952,12 @@ abstract class Model implements \JsonSerializable, \ArrayAccess
         }
         $pk = $this->getPk();
         if ($this->isUpdate) {
+            // 获取有更新的数据
+            $data = $this->getChangedData();
+
+            // 检测字段
+            $this->checkAllowField($data);
+
             // 自动更新
             $this->autoCompleteData($this->update);
 
@@ -960,9 +966,6 @@ abstract class Model implements \JsonSerializable, \ArrayAccess
                 return false;
             }
 
-            // 获取有更新的数据
-            $data = $this->getChangedData();
-
             if (empty($data) || (count($data) == 1 && is_string($pk) && isset($data[$pk]))) {
                 // 关联更新
                 if (isset($relation)) {
@@ -978,9 +981,6 @@ abstract class Model implements \JsonSerializable, \ArrayAccess
                 $where = $this->updateWhere;
             }
 
-            // 检测字段
-            $this->checkAllowField($data);
-
             // 保留主键数据
             foreach ($this->data as $key => $val) {
                 if ($this->isPk($key)) {
@@ -1008,8 +1008,12 @@ abstract class Model implements \JsonSerializable, \ArrayAccess
             $this->trigger('after_update', $this);
 
         } else {
+            // 检测字段
+            $this->checkAllowField($this->data);
+
             // 自动写入
             $this->autoCompleteData($this->insert);
+
             // 自动写入创建时间和更新时间
             if ($this->autoWriteTimestamp) {
                 if ($this->createTime && !isset($this->data[$this->createTime])) {
@@ -1024,9 +1028,6 @@ abstract class Model implements \JsonSerializable, \ArrayAccess
                 return false;
             }
 
-            // 检测字段
-            $this->checkAllowField($this->data);
-
             $result = $this->getQuery()->insert($this->data);
 
             // 获取自动增长主键