diff --git a/test/cgi/test_cgi_util.rb b/test/cgi/test_cgi_util.rb
index 5a2d07b..5baf87d 100644
--- a/test/cgi/test_cgi_util.rb
+++ b/test/cgi/test_cgi_util.rb
@@ -105,6 +105,7 @@ def test_cgi_escape_html_dont_freeze
   end
 
   def test_cgi_escape_html_large
+    return if RUBY_ENGINE == 'jruby'
     ulong_max, size_max = RbConfig::LIMITS.values_at("ULONG_MAX", "SIZE_MAX")
     return unless ulong_max < size_max # Platforms not concerned