diff --git a/app/controllers/oauth/callbacks_controller.rb b/app/controllers/oauth/callbacks_controller.rb
index 8a06a6611..84fb96b08 100644
--- a/app/controllers/oauth/callbacks_controller.rb
+++ b/app/controllers/oauth/callbacks_controller.rb
@@ -76,6 +76,7 @@ class Oauth::CallbacksController < Oauth::BaseController
         "OpenUsers::#{platform.to_s.capitalize}".constantize.create!(user: current_user, uid: uid)
       end
     end
+    Rails.logger.info("[OAuth2] session[:unionid] -> #{session[:unionid]}")
     redirect_to "/bindlogin/#{platform}"
   end