diff --git a/library/think/App.php b/library/think/App.php
index b7d59691..615be241 100644
--- a/library/think/App.php
+++ b/library/think/App.php
@@ -11,6 +11,7 @@
 
 namespace think;
 
+use think\exception\ClassNotFoundException;
 use think\exception\HttpException;
 use think\exception\HttpResponseException;
 use think\exception\RouteNotFoundException;
@@ -383,10 +384,12 @@ class App
         // 监听module_init
         Hook::listen('module_init', $request);
 
-        $instance = Loader::controller($controller, $config['url_controller_layer'], $config['controller_suffix'], $config['empty_controller']);
-        if (is_null($instance)) {
-            throw new HttpException(404, 'controller not exists:' . Loader::parseName($controller, 1));
+        try {
+            $instance = Loader::controller($controller, $config['url_controller_layer'], $config['controller_suffix'], $config['empty_controller']);
+        } catch (ClassNotFoundException $e) {
+            throw new HttpException(404, 'controller not exists:' . $e->getClass());
         }
+
         // 获取当前操作名
         $action = $actionName . $config['action_suffix'];
 
diff --git a/library/think/Loader.php b/library/think/Loader.php
index a0727fef..62e876e5 100644
--- a/library/think/Loader.php
+++ b/library/think/Loader.php
@@ -400,7 +400,7 @@ class Loader
      * @param string $layer        控制层名称
      * @param bool   $appendSuffix 是否添加类名后缀
      * @param string $empty        空控制器名称
-     * @return Object|false
+     * @return Object
      * @throws ClassNotFoundException
      */
     public static function controller($name, $layer = 'controller', $appendSuffix = false, $empty = '')
@@ -420,6 +420,8 @@ class Loader
             return App::invokeClass($class);
         } elseif ($empty && class_exists($emptyClass = self::parseClass($module, $layer, $empty, $appendSuffix))) {
             return new $emptyClass(Request::instance());
+        } else {
+            throw new ClassNotFoundException('class not exists:' . $class, $class);
         }
     }