diff --git a/README.md b/README.md
index 2661434..124e935 100644
--- a/README.md
+++ b/README.md
@@ -112,6 +112,7 @@ $ git clone git@gitlab.tp.rulingcom.com:saurabh/orbit4-5.git your_site_name
 $ cd your_site_name
 $ vim config/mongoid.yml # 所有 orbit_4_5 換成 your_site_name, :wq 存檔離開
 $ vim Gemfile # 加井字號註解掉 gem 'sassc-rails', '~>1.3.0' 並拿掉此行 #gem 'sass-rails', '~> 4.0.2' 井字號取消註解
+$ $ gem install nokogiri -v 1.7.0.1 #For Ubuntu 20.04LTS
 $ bundle install
 $ RAILS_ENV=production bundle exec rake assets:precompile
 $ bundle exec unicorn_rails -c config/unicorn.rb -D -E production