diff --git a/app/Controller/Api/V1/ArticleController.php b/app/Controller/Api/V1/ArticleController.php
index daa8e90..4c53fc6 100644
--- a/app/Controller/Api/V1/ArticleController.php
+++ b/app/Controller/Api/V1/ArticleController.php
@@ -336,7 +336,7 @@ class ArticleController extends CController
     public function uploadArticleImage()
     {
         $file = $this->request->file('image');
-        if (!$file->isValid()) {
+        if (!$file || !$file->isValid()) {
             return $this->response->fail();
         }
 
@@ -463,7 +463,7 @@ class ArticleController extends CController
         ]);
 
         $file = $this->request->file('annex');
-        if (!$file->isValid()) {
+        if (!$file || !$file->isValid()) {
             return $this->response->fail('上传文件验证失败！');
         }
 
diff --git a/app/Controller/Api/V1/TalkController.php b/app/Controller/Api/V1/TalkController.php
index ed7da6b..83ae275 100644
--- a/app/Controller/Api/V1/TalkController.php
+++ b/app/Controller/Api/V1/TalkController.php
@@ -487,7 +487,7 @@ class TalkController extends CController
         ]);
 
         $file = $this->request->file('img');
-        if (!$file->isValid()) {
+        if (!$file || !$file->isValid()) {
             return $this->response->fail();
         }
 
diff --git a/app/Controller/Api/V1/UploadController.php b/app/Controller/Api/V1/UploadController.php
index dd4ee38..f1380fb 100644
--- a/app/Controller/Api/V1/UploadController.php
+++ b/app/Controller/Api/V1/UploadController.php
@@ -98,7 +98,7 @@ class UploadController extends CController
             'split_num'   => 'required'
         ]);
 
-        if (!$file->isValid()) {
+        if (!$file || !$file->isValid()) {
             return $this->response->fail();
         }