diff --git a/Gemfile b/Gemfile
index d3508be167f..fc83c0a65bc 100644
--- a/Gemfile
+++ b/Gemfile
@@ -65,7 +65,6 @@ gem 'rubyzip'
 gem 'slim-rails'
 gem 'sorcery', '~> 0.16.2'
 gem 'sorcery-jwt'
-gem 'stringio', '3.1.0'
 gem 'stripe'
 gem 'stripe-i18n', git: 'https://github.com/komagata/stripe-i18n', branch: 'update-depencency'
 gem 'tzinfo', '~> 2.0', '>= 2.0.6'
diff --git a/Gemfile.lock b/Gemfile.lock
index c16755b9596..5892edcd074 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -679,7 +679,6 @@ DEPENDENCIES
   sorcery-jwt
   spring
   spring-watcher-listen (~> 2.0.0)
-  stringio (= 3.1.0)
   stripe
   stripe-i18n!
   syntax_suggest