diff --git a/app/controllers/oauth_controller.rb b/app/controllers/oauth_controller.rb
index 7ed65d53c..1cdeb4aa3 100644
--- a/app/controllers/oauth_controller.rb
+++ b/app/controllers/oauth_controller.rb
@@ -62,7 +62,11 @@ class OauthController < ApplicationController
     email = params[:mail]
     password = params[:password]
     callback_url =  params[:callback_url]
-    platform = params[:plathform] || 'forge'
+    platform = params[:plathform] || 'educoder'
+
+    if User.where(mail: email).exists?
+      render_error("该邮箱已使用过.") and return
+    end
 
     result = autologin_register(login, email, password, platform)
     logger.info "[Oauth educoer] =====#{result}"
diff --git a/app/views/oauth/register.html.erb b/app/views/oauth/register.html.erb
index df3b1eb67..d9b39543c 100644
--- a/app/views/oauth/register.html.erb
+++ b/app/views/oauth/register.html.erb
@@ -46,6 +46,9 @@
     if(!password){
       $(".passwordCheck span").html("请输入账号密码");
       return;
+    }else if(password.length < 8){
+      $(".passwordCheck span").html("密码最少为8位数");
+      return;
     }else{
       $(".passwordCheck span").html("");
     }
@@ -57,11 +60,19 @@
       success: function(data) {
         console.log(data)
         if (data) {
+          if(data.message){
+            $(".emailCheck span").html("该邮箱已存在.");
+            return;
+          }
           // data.redirect contains the string URL to redirect to
           // window.location.href = "<%#= params[:callback_url] %>";
            window.location.href = data.callback_url;
         }
-      }
+      },
+    	error: function (data) {
+    		console.log('ajax error handling',data);
+    	}
+
     });
   }
 </script>