diff --git a/lib/tasks/zip_pack.rake b/lib/tasks/zip_pack.rake
index e3215090b..9cfb36a8e 100644
--- a/lib/tasks/zip_pack.rake
+++ b/lib/tasks/zip_pack.rake
@@ -38,9 +38,8 @@ namespace :zip_pack do
 
   def zip_homework_pdf homeworks, folder, parallel_size
     Dir.mkdir(folder) unless File.directory?(folder)
-    homeworks = homeworks.includes(:score_student_works)
 
-    Parallel.each(homeworks, in_processes: 2) do |homework|
+    homeworks.includes(:score_student_works).each do |homework|
       out_file_name = "#{Time.now.strftime("%Y%m%d%H%M%S").to_s}-#{homework.course_id}-#{homework.name}.zip"
       out_file_name.gsub!(" ", "-")
       out_file_name.gsub!("/", "_")
@@ -51,21 +50,26 @@ namespace :zip_pack do
 
       if student_works.size > 0
         pdfs = []
+        file_paths = []
+        student_works.find_in_batches(batch_size: 500) do |sw|
+          Parallel.each(sw, in_threads: parallel_size) do |student_work|
+            export = ExportShixunReportService.new(homework, student_work)
+            pdf = export.to_pdf
+            pdfs << pdf
+            file_paths << {filename: export.filename, path: pdf.path}
+            puts "out: #{export.filename}_#{pdf.path}"
+          end
+        end
+
         Zip::File.open(zipfile_name, Zip::File::CREATE) do |zip|
-          student_works.find_in_batches(batch_size: 500) do |sw|
-            Parallel.each(sw, in_processes: parallel_size) do |student_work|
-              export = ExportShixunReportService.new(homework, student_work)
-              pdf = export.to_pdf
-              pdfs << pdf
-              begin
-                zip.add(export.filename, pdf.path)
-                puts "out: #{export.filename}_#{pdf.path}"
-              rescue => ex
-                Rails.logger.error(ex.message)
+          file_paths.each do |pdf|
+            begin
+              zip.add(pdf[:filename], pdf[:path])
+            rescue => ex
+              Rails.logger.error(ex.message)
 
-                zip.get_output_stream('FILE_NOTICE.txt'){|os| os.write("文件重复:#{export.filename}") }
-                next
-              end
+              zip.get_output_stream('FILE_NOTICE.txt'){|os| os.write("文件重复:#{export.filename}") }
+              next
             end
           end
         end