diff --git a/app/libs/util/uuid.rb b/app/libs/util/uuid.rb
index 2f6757139..8147ff3a3 100644
--- a/app/libs/util/uuid.rb
+++ b/app/libs/util/uuid.rb
@@ -2,8 +2,26 @@ module Util
   module UUID
     module_function
 
+    DCODES = %W(2 3 4 5 6 7 8 9 a b c f e f g h i j k l m n o p q r s t u v w x y z)
+
     def time_uuid(format: '%Y%m%d%H%M%S', suffix: 8)
       "#{Time.zone.now.strftime(format)}#{Random.rand(10**suffix).to_i}"
     end
+
+    # 随机生成字符
+    def generate_identifier(container, num, pre='')
+      code = DCODES.sample(num).join
+      if container == User
+        while container.exists?(login: pre+code) do
+          code = DCODES.sample(num).join
+        end
+      else
+        while container.exists?(identifier: code) do
+          code = DCODES.sample(num).join
+        end
+      end
+      code
+    end
+
   end
 end
diff --git a/app/services/subjects/copy_subject_service.rb b/app/services/subjects/copy_subject_service.rb
index 99f5dcdc5..924eb10ef 100644
--- a/app/services/subjects/copy_subject_service.rb
+++ b/app/services/subjects/copy_subject_service.rb
@@ -60,6 +60,7 @@ class Subjects::CopySubjectService < ApplicationService
     to_shixun = Shixun.new
     to_shixun.attributes = shixun.attributes.dup.except('id', 'user_id', 'identifier', 'homepage_show',
                                                         'use_scope', 'averge_star', 'myshixuns_count')
+    to_shixun.identifier = Util::UUID.generate_identifier(Shixun, 8)
     to_shixun.user_id = user_id
     to_shixun.save!