diff --git a/android/Gemfile b/android/Gemfile
index cdd3a6b3..5f5b8322 100644
--- a/android/Gemfile
+++ b/android/Gemfile
@@ -1,6 +1,7 @@
 source "https://rubygems.org"
 
 gem "fastlane"
+gem 'nkf', '0.2.0'
 
 plugins_path = File.join(File.dirname(__FILE__), 'fastlane', 'Pluginfile')
 eval_gemfile(plugins_path) if File.exist?(plugins_path)
diff --git a/ios/Gemfile b/ios/Gemfile
index 21cb5dfc..cb7538c4 100644
--- a/ios/Gemfile
+++ b/ios/Gemfile
@@ -5,3 +5,4 @@ gem 'cocoapods', '1.14.3'
 gem 'public_suffix', '~> 4.0'
 plugins_path = File.join(File.dirname(__FILE__), 'fastlane', 'Pluginfile')
 eval_gemfile(plugins_path) if File.exist?(plugins_path)
+gem 'nkf', '0.2.0'