diff --git a/app/controllers/admins/disciplines_controller.rb b/app/controllers/admins/disciplines_controller.rb
index 598ab7386..b7b3152fb 100644
--- a/app/controllers/admins/disciplines_controller.rb
+++ b/app/controllers/admins/disciplines_controller.rb
@@ -7,7 +7,7 @@ class Admins::DisciplinesController < Admins::BaseController
   def create
     name = params[:name].to_s.strip
     return render_error('名称重复') if Discipline.where(name: name).exists?
-    Discipline.create!(name: name, position: Discipline.all.pluck(:position).max + 1)
+    Discipline.create!(name: name, position: Discipline.all.pluck(:position).max.to_i + 1)
     render_ok
   end
 
@@ -46,7 +46,7 @@ class Admins::DisciplinesController < Admins::BaseController
   end
 
   def adjust_position
-    max_position = Discipline.all.pluck(:position).max
+    max_position = Discipline.all.pluck(:position).max.to_i
     opr = params[:opr] || "down"
     if (params[:opr] == "up" && current_discipline.position == 1) || (params[:opr] == "down" && current_discipline.position == max_position)
       @message = "超出范围"
diff --git a/app/controllers/admins/sub_disciplines_controller.rb b/app/controllers/admins/sub_disciplines_controller.rb
index a60f497e5..61f644a91 100644
--- a/app/controllers/admins/sub_disciplines_controller.rb
+++ b/app/controllers/admins/sub_disciplines_controller.rb
@@ -9,7 +9,7 @@ class Admins::SubDisciplinesController < Admins::BaseController
     name = params[:name].to_s.strip
     return render_error('名称不能为空') if name.blank?
     return render_error('名称重复') if current_discipline.sub_disciplines.where(name: name).exists?
-    SubDiscipline.create!(name: name, discipline_id: current_discipline.id, position: current_discipline.sub_disciplines.pluck(:position).max + 1)
+    SubDiscipline.create!(name: name, discipline_id: current_discipline.id, position: current_discipline.sub_disciplines.pluck(:position).max.to_i + 1)
     render_ok
   end
 
@@ -47,7 +47,7 @@ class Admins::SubDisciplinesController < Admins::BaseController
 
   def adjust_position
     discipline = current_sub_discipline.discipline
-    max_position = discipline.sub_disciplines.pluck(:position).max
+    max_position = discipline.sub_disciplines.pluck(:position).max.to_i
     opr = params[:opr] || "down"
     if (params[:opr] == "up" && current_sub_discipline.position == 1) || (params[:opr] == "down" && current_sub_discipline.position == max_position)
       @message = "超出范围"
diff --git a/app/controllers/admins/tag_disciplines_controller.rb b/app/controllers/admins/tag_disciplines_controller.rb
index c10f63884..c8e14dbd8 100644
--- a/app/controllers/admins/tag_disciplines_controller.rb
+++ b/app/controllers/admins/tag_disciplines_controller.rb
@@ -9,7 +9,7 @@ class Admins::TagDisciplinesController < Admins::BaseController
     name = params[:name].to_s.strip
     return render_error('名称重复') if current_sub_discipline.tag_disciplines.where(name: name).exists?
     TagDiscipline.create!(name: name, sub_discipline_id: current_sub_discipline.id, user_id: current_user.id,
-                          position: current_sub_discipline.tag_disciplines.pluck(:position).max + 1)
+                          position: current_sub_discipline.tag_disciplines.pluck(:position).max.to_i + 1)
     render_ok
   end
 
@@ -42,7 +42,7 @@ class Admins::TagDisciplinesController < Admins::BaseController
 
   def adjust_position
     sub_discipline = current_tag_discipline.sub_discipline
-    max_position = sub_discipline.tag_disciplines.pluck(:position).max
+    max_position = sub_discipline.tag_disciplines.pluck(:position).max.to_i
     opr = params[:opr] || "down"
     if (params[:opr] == "up" && current_tag_discipline.position == 1) || (params[:opr] == "down" && current_tag_discipline.position == max_position)
       @message = "超出范围"
diff --git a/app/controllers/tag_disciplines_controller.rb b/app/controllers/tag_disciplines_controller.rb
index c80071824..2db5abf28 100644
--- a/app/controllers/tag_disciplines_controller.rb
+++ b/app/controllers/tag_disciplines_controller.rb
@@ -5,7 +5,7 @@ class TagDisciplinesController < ApplicationController
     sub_discipline = SubDiscipline.find_by!(id: params[:sub_discipline_id])
     tip_exception("重复的知识点") if sub_discipline.tag_disciplines.exists?(name: params[:name].to_s.strip)
     tag_discipline = TagDiscipline.create!(name: params[:name].to_s.strip, sub_discipline: sub_discipline, user_id: current_user.id,
-                                           position: sub_discipline.tag_disciplines.pluck(:position).max + 1)
+                                           position: sub_discipline.tag_disciplines.pluck(:position).max.to_i + 1)
     render_ok({tag_discipline_id: tag_discipline.id})
   end
 end
\ No newline at end of file
diff --git a/app/services/admins/import_discipline_service.rb b/app/services/admins/import_discipline_service.rb
index 37cb5b7e5..a18922135 100644
--- a/app/services/admins/import_discipline_service.rb
+++ b/app/services/admins/import_discipline_service.rb
@@ -29,14 +29,14 @@ class Admins::ImportDisciplineService < ApplicationService
     return unless discipline_name.present?
     discipline = Discipline.find_by(name: discipline_name)
     if discipline.blank?
-      discipline = Discipline.create!(name: discipline_name, position: Discipline.all.pluck(:position).max + 1)
+      discipline = Discipline.create!(name: discipline_name, position: Discipline.all.pluck(:position).max.to_i + 1)
       count += 1
     end
 
     if sub_discipline_name.present?
       sub_discipline = SubDiscipline.find_by(name: discipline_name, discipline: discipline)
       if sub_discipline.blank?
-        SubDiscipline.create!(name: sub_discipline_name, discipline: discipline, position: discipline.sub_disciplines.pluck(:position).max + 1)
+        SubDiscipline.create!(name: sub_discipline_name, discipline: discipline, position: discipline.sub_disciplines.pluck(:position).max.to_i + 1)
         count += 1
       end
     end