diff --git a/library/think/App.php b/library/think/App.php
index 7e54f913..573e1289 100644
--- a/library/think/App.php
+++ b/library/think/App.php
@@ -94,15 +94,18 @@ class App
 
             $request->filter($config['default_filter']);
 
-            // 开启多语言机制
             if ($config['lang_switch_on']) {
-                // 获取当前语言
-                $request->langset(Lang::detect());
-                // 加载系统语言包
-                Lang::load(THINK_PATH . 'lang' . DS . $request->langset() . EXT);
-                if (!$config['app_multi_module']) {
-                    Lang::load(APP_PATH . 'lang' . DS . $request->langset() . EXT);
-                }
+                // 开启多语言机制 检测当前语言
+                Lang::detect();
+            } else {
+                // 读取默认语言
+                Lang::range($config['default_lang']);
+            }
+            $request->langset(Lang::range());
+            // 加载系统语言包
+            Lang::load(THINK_PATH . 'lang' . DS . $request->langset() . EXT);
+            if (!$config['app_multi_module']) {
+                Lang::load(APP_PATH . 'lang' . DS . $request->langset() . EXT);
             }
 
             // 获取应用调度信息
@@ -496,7 +499,7 @@ class App
             }
 
             // 加载当前模块语言包
-            if ($config['lang_switch_on'] && $module) {
+            if ($module) {
                 Lang::load($path . 'lang' . DS . Request::instance()->langset() . EXT);
             }
         }
diff --git a/library/think/Lang.php b/library/think/Lang.php
index 4530b62a..1e7bf197 100644
--- a/library/think/Lang.php
+++ b/library/think/Lang.php
@@ -81,10 +81,8 @@ class Lang
                 // 记录加载信息
                 App::$debug && Log::record('[ LANG ] ' . $_file, 'info');
                 $_lang = include $_file;
-            } else {
-                $_lang = [];
+                $lang  = array_change_key_case($_lang) + $lang;
             }
-            $lang = array_change_key_case($_lang) + $lang;
         }
         if (!empty($lang)) {
             self::$lang[$range] = $lang + self::$lang[$range];
diff --git a/library/think/exception/Handle.php b/library/think/exception/Handle.php
index ad05c70b..8b6e6c40 100644
--- a/library/think/exception/Handle.php
+++ b/library/think/exception/Handle.php
@@ -203,10 +203,6 @@ class Handle
         if (IS_CLI) {
             return $message;
         }
-        // 导入语言包
-        if (!Config::get('lang_switch_on')) {
-            Lang::load(THINK_PATH . 'lang' . DS . Lang::detect() . EXT);
-        }
 
         if (strpos($message, ':')) {
             $name    = strstr($message, ':', true);