diff --git a/app/controllers/panel/announcement/back_end/bulletins_controller.rb b/app/controllers/panel/announcement/back_end/bulletins_controller.rb
index f44c7cb..de369ee 100644
--- a/app/controllers/panel/announcement/back_end/bulletins_controller.rb
+++ b/app/controllers/panel/announcement/back_end/bulletins_controller.rb
@@ -10,6 +10,7 @@ class Panel::Announcement::BackEnd::BulletinsController < OrbitBackendController
   end
 
   def preview
+    params['bulletin']['image'] = nil
     bulletin = Bulletin.new params
     @preview_obj = bulletin.to_preview
     @preview_obj.save