diff --git a/dev-ruby/pdf-core/pdf-core-0.9.0.ebuild b/dev-ruby/pdf-core/pdf-core-0.9.0.ebuild
index c3afffa2aeded..2907316a9ce09 100644
--- a/dev-ruby/pdf-core/pdf-core-0.9.0.ebuild
+++ b/dev-ruby/pdf-core/pdf-core-0.9.0.ebuild
@@ -3,7 +3,7 @@
 
 EAPI=7
 
-USE_RUBY="ruby26 ruby27 ruby30"
+USE_RUBY="ruby26 ruby27 ruby30 ruby31"
 
 RUBY_FAKEGEM_RECIPE_TEST="rspec3"