diff --git a/app/controllers/homework_commons_controller.rb b/app/controllers/homework_commons_controller.rb
index 6bdd726dd..c2e09fe2b 100644
--- a/app/controllers/homework_commons_controller.rb
+++ b/app/controllers/homework_commons_controller.rb
@@ -87,7 +87,7 @@ class HomeworkCommonsController < ApplicationController
     end
     @task_count = @homework_commons.size
 
-    order_str = @homework_type == 4 ? "position DESC" : "IF(ISNULL(homework_commons.publish_time),0,1), homework_commons.publish_time DESC,
+    order_str = @homework_type == 4 ? "homework_commons.position DESC" : "IF(ISNULL(homework_commons.publish_time),0,1), homework_commons.publish_time DESC,
                                                   homework_commons.created_at DESC"
     @homework_commons = @homework_commons.order(order_str).page(page).per(15)