diff --git a/Gemfile b/Gemfile
index c9e9cbf..d31676f 100644
--- a/Gemfile
+++ b/Gemfile
@@ -13,7 +13,7 @@ end
 
 group :optional do
   # epubcheck-ruby might be safe to be converted into runtime dependency, but could have issues when packaged into asciidoctorj-epub3
-  gem 'epubcheck-ruby', '~> 5.0.0.0'
+  gem 'epubcheck-ruby', '~> 5.1.0.0'
   # Kindlegen is unavailable neither for 64-bit MacOS nor for ARM
   gem 'kindlegen', '~> 3.1.0' unless RbConfig::CONFIG['host_os'] =~ /darwin/
 end