diff --git a/rswag-ui/open_api-rswag-ui.gemspec b/rswag-ui/open_api-rswag-ui.gemspec
index a9668ae..a5712d0 100644
--- a/rswag-ui/open_api-rswag-ui.gemspec
+++ b/rswag-ui/open_api-rswag-ui.gemspec
@@ -13,6 +13,6 @@ Gem::Specification.new do |s|
 
   s.files = Dir.glob("{lib,node_modules}/**/*") + ["MIT-LICENSE", "Rakefile" ]
 
-  s.add_dependency 'actionpack', '>=3.1'
-  s.add_dependency 'railties', '>= 3.1'
+  s.add_dependency 'actionpack', '>=3.1', '< 7.0'
+  s.add_dependency 'railties', '>= 3.1', '< 7.0'
 end