ワリと時間かかったのでメモ。 config/environments/production.rb config.paperclip_defaults = { storage: :s3, s3_host_alias: 'your.cloudfront.net', path: '/:class/:attachment/:id/:style/:hash.:extension', url: ':s3_alias_url', s3_host_name: 's3-ap-northeast-1.amazonaws.com', s3_protocol: '', s3_credentials: { bucket: 'your_backet_name' } } config/initializers/paperclip.rb Paperclip::Attachment.default_options[:has