diff --git a/Gemfile b/Gemfile
index 041300665..34868db9a 100644
--- a/Gemfile
+++ b/Gemfile
@@ -10,6 +10,6 @@ gem 'asciidoctor-epub3', '1.5.0.alpha.18'
 gem 'asciidoctor-pdf', '1.5.3'
 
 gem 'coderay', '1.1.3'
-gem 'pygments.rb', '1.2.1'
+gem 'pygments.rb', '2.3.1'
 gem 'thread_safe', '0.3.6'
 gem 'epubcheck', '3.0.1'