diff --git a/lib/redmine/preparation.rb b/lib/redmine/preparation.rb
index d006923bc..c435a9cf6 100644
--- a/lib/redmine/preparation.rb
+++ b/lib/redmine/preparation.rb
@@ -395,7 +395,7 @@ module Redmine
 
       WikiFormatting.map do |format|
         format.register :textile
-        format.register :markdown if Object.const_defined?(:Redcarpet)
+        format.register :markdown, label: 'Markdown (deprecated)' if Object.const_defined?(:Redcarpet)
         if Object.const_defined?(:CommonMarker)
           format.register :common_mark, label: 'CommonMark Markdown (GitHub Flavored)'
         end