diff --git a/app/controllers/oauth_controller.rb b/app/controllers/oauth_controller.rb
index 4dd2e6fd..714bd610 100644
--- a/app/controllers/oauth_controller.rb
+++ b/app/controllers/oauth_controller.rb
@@ -185,7 +185,7 @@ class OauthController < ApplicationController
       ActiveRecord::Base.transaction do
         # 如果Educoder中已存在与该OpenI用户的邮箱相同的用户，则会直接跳转到登录educoder的登录页面
         existing_user = User.find_by_mail(email)
-        break if existing_user.present?
+        break if existing_user.present? && email.present?
 
         user = User.new(lastname: name, mail: email, mail_notification: email)
         user.login = generate_login('m')