diff --git a/app/controllers/courses_controller.rb b/app/controllers/courses_controller.rb
index 210ac8f3d..3b25438df 100644
--- a/app/controllers/courses_controller.rb
+++ b/app/controllers/courses_controller.rb
@@ -695,13 +695,11 @@ class CoursesController < ApplicationController
       # 显示老师和助教的活动
       # @authors = searchTeacherAndAssistant(@course)
       @authors = course_all_member(@course)
-      #TODO 貌似删除操作不会更新缓存 还是先不用缓存吧
-      # Dir.glob("#{Rails.root}/app/models/*.rb").sort.each { |file| require file }
       events = []
-      # key = "course_events_#{@course.id}".to_sym
-      # if Rails.env.production? && Setting.course_cahce_enabled?
-      #   events = Rails.cache.read(key) || []
-      # end
+      key = "course_events_#{@course.id}".to_sym
+      if Rails.env.production? && Setting.course_cahce_enabled?
+        events = Rails.cache.read(key) || []
+      end
       if events.empty? 
         @authors.each do |author|
           @activity = Redmine::Activity::Fetcher.new(User.current, :course => @course,
@@ -717,7 +715,7 @@ class CoursesController < ApplicationController
             events += @activity.events(@days, @course.created_at, :is_public => 1)
           end
         end
-        # Rails.cache.write(key, events) if Rails.env.production? && Setting.course_cahce_enabled?
+        Rails.cache.write(key, events) if Rails.env.production? && Setting.course_cahce_enabled?
       end
     else
     # @author = @course.teacher
diff --git a/lib/trustie/cache/clear_course_event.rb b/lib/trustie/cache/clear_course_event.rb
index a5f44bf45..cc643020d 100644
--- a/lib/trustie/cache/clear_course_event.rb
+++ b/lib/trustie/cache/clear_course_event.rb
@@ -6,6 +6,7 @@ module Trustie
       def self.included(base)
         base.class_eval{
           after_create :clear_course_events
+          after_destroy :clear_course_events
         }
       end