diff --git a/lib/tasks/homework_evaluation.rake b/lib/tasks/homework_evaluation.rake
new file mode 100644
index 000000000..691493dc8
--- /dev/null
+++ b/lib/tasks/homework_evaluation.rake
@@ -0,0 +1,54 @@
+#coding=utf-8
+
+namespace :homework_evaluation do
+  desc "start evaluation"
+  def get_assigned_homeworks(student_works, n, index)
+    student_works += student_works
+    student_works[index + 1 .. index + n]
+  end
+  #自动开启匿评的任务
+  task :start_evaluation => :environment do
+    homework_detail_manuals = HomeworkDetailManual.where("evaluation_start = '#{Date.today}'")
+    homework_detail_manuals.each do |homework_detail_manual|
+      homework_common = homework_detail_manual.homework_common
+      if homework_detail_manual.comment_status == 1  #新建状态才可开启匿评
+        student_works = homework_common.student_works
+        if student_works && student_works.size >= 2
+          student_works.each_with_index do |work, index|
+            user = work.user
+            n = homework_detail_manual.evaluation_num
+            n = n < student_works.size ? n : student_works.size - 1
+            assigned_homeworks = get_assigned_homeworks(student_works, n, index)
+            assigned_homeworks.each do |h|
+              student_works_evaluation_distributions = StudentWorksEvaluationDistribution.new(user_id: user.id, student_work_id: h.id)
+              student_works_evaluation_distributions.save
+            end
+          end
+          homework_detail_manual.update_column('comment_status', 2)
+          # 匿评开启消息邮件通知
+        else
+          #作业数小于2，启动失败
+        end
+      end
+    end
+  end
+
+  #自动关闭匿评的任务
+  task :end_evaluation => :environment do
+    homework_detail_manuals = HomeworkDetailManual.where("evaluation_end = '#{Date.today}'")
+    homework_detail_manuals.each do |homework_detail_manual|
+      homework_common = homework_detail_manual.homework_common
+      if homework_detail_manual.comment_status == 2 #开启匿评状态才可关闭匿评
+        #计算缺评扣分
+        work_ids = "(" + homework_common.student_works.map(&:id).join(",") + ")"
+        homework_common.student_works.each do |student_work|
+          absence_penalty_count = student_work.user.student_works_evaluation_distributions.where("student_work_id IN #{work_ids}").count - student_work.user.student_works_scores.where("student_work_id IN #{work_ids}").count
+          student_work.absence_penalty = absence_penalty_count > 0 ? absence_penalty_count * homework_detail_manuals.absence_penalty : 0
+          student_work.save
+        end
+        homework_detail_manual.update_column('comment_status', 3)
+        # 匿评关闭消息邮件通知
+      end
+    end
+  end
+end