diff --git a/app/controllers/admins/projects_controller.rb b/app/controllers/admins/projects_controller.rb
index 5589c66c..f5f210a0 100644
--- a/app/controllers/admins/projects_controller.rb
+++ b/app/controllers/admins/projects_controller.rb
@@ -43,8 +43,12 @@ class Admins::ProjectsController < Admins::BaseController
   def destroy
     project = Project.find_by!(id: params[:id])
     ActiveRecord::Base.transaction do
+      close_fork_pull_requests_by(project)
       Gitea::Repository::DeleteService.new(project.owner, project.identifier, current_user.gitea_token).call
       project.destroy!
+      project.forked_projects.update_all(forked_from_project_id: nil)
+      # 如果该项目有所属的项目分类以及为私有项目，需要更新对应数量
+      project.project_category.decrement!(:private_projects_count, 1) if project.project_category.present? && !project.is_public
       # render_delete_success
       UserAction.create(action_id: project.id, action_type: "DestroyProject", user_id: current_user.id, :ip => request.remote_ip, data_bank: project.attributes.to_json)
       redirect_to admins_projects_path
@@ -63,4 +67,19 @@ class Admins::ProjectsController < Admins::BaseController
   def project_update_params 
     params.require(:project).permit(:is_pinned, :recommend, :recommend_index)
   end
+
+  def close_fork_pull_requests_by(project)
+    open_pull_requests = PullRequest.where(fork_project_id: project.id)
+    if open_pull_requests.present?
+      open_pull_requests.each do |pull_request|
+        closed = PullRequests::CloseService.call(pull_request&.project.owner, pull_request&.project.repository, pull_request, current_user)
+        if closed === true
+          pull_request.project_trends.create!(user: current_user, project: pull_request&.project,action_type: ProjectTrend::CLOSE)
+          # 合并请求下issue处理为关闭
+          pull_request.issue&.update_attributes!({status_id:5})
+          SendTemplateMessageJob.perform_later('PullRequestClosed', current_user.id, pull_request.id) if Site.has_notice_menu?
+        end
+      end 
+    end
+  end
 end
\ No newline at end of file
diff --git a/app/controllers/projects_controller.rb b/app/controllers/projects_controller.rb
index 12b668d9..6485ddef 100644
--- a/app/controllers/projects_controller.rb
+++ b/app/controllers/projects_controller.rb
@@ -258,6 +258,7 @@ class ProjectsController < ApplicationController
   def destroy
     if current_user.admin? || @project.manager?(current_user)
       ActiveRecord::Base.transaction do
+        close_fork_pull_requests_by(@project)
         Gitea::Repository::DeleteService.new(@project.owner, @project.identifier,current_user.gitea_token).call
         @project.destroy!
         @project.forked_projects.update_all(forked_from_project_id: nil)
@@ -408,4 +409,19 @@ class ProjectsController < ApplicationController
       render_unauthorized('你还未登录.')
     end
   end
+
+  def close_fork_pull_requests_by(project)
+    open_pull_requests = PullRequest.where(fork_project_id: project.id)
+    if open_pull_requests.present?
+      open_pull_requests.each do |pull_request|
+        closed = PullRequests::CloseService.call(pull_request&.project.owner, pull_request&.project.repository, pull_request, current_user)
+        if closed === true
+          pull_request.project_trends.create!(user: current_user, project: pull_request&.project,action_type: ProjectTrend::CLOSE)
+          # 合并请求下issue处理为关闭
+          pull_request.issue&.update_attributes!({status_id:5})
+          SendTemplateMessageJob.perform_later('PullRequestClosed', current_user.id, pull_request.id) if Site.has_notice_menu?
+        end
+      end 
+    end
+  end
 end