diff --git a/app/controllers/challenges_controller.rb b/app/controllers/challenges_controller.rb
index 0f6532372..8cb68b1d4 100644
--- a/app/controllers/challenges_controller.rb
+++ b/app/controllers/challenges_controller.rb
@@ -234,18 +234,21 @@ class ChallengesController < ApplicationController
   #   {...}, ...]
   #}
   def crud_answer
-    raise '参考答案不能为空' if params[:challenge_answer].empty?
-    raise '占比之和必须为100%' if params[:challenge_answer].map{|a| a[:score]}.sum != 100
-    ActiveRecord::Base.transaction do
-      @challenge.challenge_answers.destroy_all if @challenge.challenge_answers
-      params[:challenge_answer].each_with_index do |answer, index|
-        # 内容为空不保存
-        next if answer[:contents].blank?
-        ChallengeAnswer.create(name: answer[:name], contents: answer[:contents],
-                               level: index+1, score: answer[:score], challenge_id: @challenge.id)
+    if @challenge.challenge_answers && params[:challenge_answer].blank?
+      @challenge.challenge_answers.destroy_all
+    else
+      raise '参考答案不能为空' if params[:challenge_answer].empty?
+      raise '占比之和必须为100%' if params[:challenge_answer].map{|a| a[:score]}.sum != 100
+      ActiveRecord::Base.transaction do
+        @challenge.challenge_answers.destroy_all if @challenge.challenge_answers
+        params[:challenge_answer].each_with_index do |answer, index|
+          # 内容为空不保存
+          next if answer[:contents].blank?
+          ChallengeAnswer.create(name: answer[:name], contents: answer[:contents],
+                                 level: index+1, score: answer[:score], challenge_id: @challenge.id)
+        end
       end
     end
-
   end
 
   # 查看参考答案接口
diff --git a/app/views/challenges/crud_answer.json.jbuilder b/app/views/challenges/crud_answer.json.jbuilder
index b11268d99..e16f09423 100644
--- a/app/views/challenges/crud_answer.json.jbuilder
+++ b/app/views/challenges/crud_answer.json.jbuilder
@@ -1,2 +1,2 @@
 json.status 1
-json.message "创建参考答案成功"
\ No newline at end of file
+json.message "操作成功"
\ No newline at end of file