diff --git a/lib/redmine.rb b/lib/redmine.rb
index 9392558f5..a44a72ffe 100644
--- a/lib/redmine.rb
+++ b/lib/redmine.rb
@@ -5,7 +5,7 @@ require 'redmine/acts_as_watchable/init'
 require 'redmine/acts_as_event/init'
 
 begin
-  require_library_or_gem 'rmagick' unless Object.const_defined?(:Magick)
+  require_library_or_gem 'RMagick' unless Object.const_defined?(:Magick)
 rescue LoadError
   # RMagick is not available
 end