diff --git a/app/helpers/dmsf_helper.rb b/app/helpers/dmsf_helper.rb
index 94c0d225..808aaf8e 100644
--- a/app/helpers/dmsf_helper.rb
+++ b/app/helpers/dmsf_helper.rb
@@ -21,6 +21,7 @@
 
 require 'tmpdir'
 require 'digest/md5'
+require 'csv'
 
 module DmsfHelper
   include Redmine::I18n