diff --git a/app/views/layouts/admin.html.erb b/app/views/layouts/admin.html.erb
index a05dfe952..3be8247b9 100644
--- a/app/views/layouts/admin.html.erb
+++ b/app/views/layouts/admin.html.erb
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html>
+<html lang="zh-Hans-CN">
   <head>
     <title>ForgePlus后台管理</title>
     <meta charset="utf-8">
diff --git a/app/views/layouts/college.html.erb b/app/views/layouts/college.html.erb
index a88b59235..d7e1e535d 100644
--- a/app/views/layouts/college.html.erb
+++ b/app/views/layouts/college.html.erb
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html>
+<html lang="zh-Hans-CN">
 <head>
   <title>EduCoder</title>
   <meta charset="utf-8">
diff --git a/app/views/layouts/cooperative.html.erb b/app/views/layouts/cooperative.html.erb
index 93be04708..a200eefa7 100644
--- a/app/views/layouts/cooperative.html.erb
+++ b/app/views/layouts/cooperative.html.erb
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html>
+<html lang="zh-Hans-CN">
   <head>
     <title><%= current_laboratory.laboratory_setting&.name || 'GitLink' %>-后台管理</title>
     <meta charset="utf-8">
diff --git a/app/views/layouts/doorkeeper/application.html.erb b/app/views/layouts/doorkeeper/application.html.erb
index 637859307..b7dbee9e9 100644
--- a/app/views/layouts/doorkeeper/application.html.erb
+++ b/app/views/layouts/doorkeeper/application.html.erb
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html>
+<html lang="zh-Hans-CN">
 
 <head>
   <title>GitLink oauth2 认证</title>
@@ -138,4 +138,4 @@
 </div>
 </body>
 
-</html>
\ No newline at end of file
+</html>
diff --git a/app/views/layouts/mailer.html.erb b/app/views/layouts/mailer.html.erb
index 9be96a548..b53db793a 100644
--- a/app/views/layouts/mailer.html.erb
+++ b/app/views/layouts/mailer.html.erb
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html>
+<html lang="zh-Hans-CN">
   <head>
     <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
     <style>
diff --git a/app/views/layouts/oauth_register.html.erb b/app/views/layouts/oauth_register.html.erb
index 1e43ddbea..7dff461dd 100644
--- a/app/views/layouts/oauth_register.html.erb
+++ b/app/views/layouts/oauth_register.html.erb
@@ -1,4 +1,4 @@
-<html>
+<html lang="zh-Hans-CN">
   <head>
     <%= csrf_meta_tags %>
     <%= csp_meta_tag %>
