diff --git a/lib/cgi/util.rb b/lib/cgi/util.rb
index 07deeda266..389a04acd2 100644
--- a/lib/cgi/util.rb
+++ b/lib/cgi/util.rb
@@ -3,4 +3,5 @@
 require "cgi/escape"
 warn <<-WARNING, uplevel: Gem::BUNDLED_GEMS.uplevel if $VERBOSE
 CGI::Util is removed from Ruby 3.5. Please use cgi/escape instead for CGI.escape and CGI.unescape features.
+If you are using CGI.parse, please install and use the cgi gem instead.
 WARNING