diff --git a/app/controllers/shixuns_controller.rb b/app/controllers/shixuns_controller.rb
index a809e8d2b..e7a1a8411 100644
--- a/app/controllers/shixuns_controller.rb
+++ b/app/controllers/shixuns_controller.rb
@@ -414,7 +414,7 @@ class ShixunsController < ApplicationController
 
 	# 更新背景知识
 	def update_propaedeutics
-		@shixun.update_column(:propaedeutics, params[:content])
+		@shixun.shixun_info.update_column(:propaedeutics, params[:content])
 	end
 
 	# 获取推荐实训接口 2个热门实训 + 2个最新实训