diff --git a/app/controllers/subjects_controller.rb b/app/controllers/subjects_controller.rb
index 431423d87..df6ee31de 100644
--- a/app/controllers/subjects_controller.rb
+++ b/app/controllers/subjects_controller.rb
@@ -149,7 +149,7 @@ class SubjectsController < ApplicationController
   end
 
   def choose_subject_shixun
-    @search = params[:search].strip
+    @search = params[:search].strip if params[:search]
     @type = params[:type]
     # 超级管理员用户显示所有未隐藏的实训、非管理员显示合作团队用户的实训（对本单位公开且未隐藏）
     if current_user.admin?