diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 6c2704b..7a4b54d 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -15,6 +15,10 @@ jobs:
           - gemfiles/rails_5.1_active_admin_1.x.gemfile
           - gemfiles/rails_5.x_active_admin_1.x.gemfile
           - gemfiles/rails_5.x_active_admin_2.x.gemfile
+          - gemfiles/rails_6.x_active_admin_2.x.gemfile
+        include:
+          - ruby-version: '3.0'
+            gemfile: gemfiles/rails_6.x_active_admin_2.x.gemfile
 
     env:
       BUNDLE_GEMFILE: ${{ matrix.gemfile }}
diff --git a/Appraisals b/Appraisals
index e2c115d..16ac6de 100644
--- a/Appraisals
+++ b/Appraisals
@@ -11,4 +11,9 @@ end
 appraise 'rails-5.x-active-admin-2.x' do
   gem 'rails', '~> 5.2'
   gem 'activeadmin', '~> 2.0'
+end
+
+appraise 'rails-6.x-active-admin-2.x' do
+  gem 'rails', '~> 6.1'
+  gem 'activeadmin', '~> 2.0'
 end
\ No newline at end of file
diff --git a/activeadmin-searchable_select.gemspec b/activeadmin-searchable_select.gemspec
index 2a773ff..9406feb 100644
--- a/activeadmin-searchable_select.gemspec
+++ b/activeadmin-searchable_select.gemspec
@@ -14,7 +14,7 @@ Gem::Specification.new do |spec|
   spec.files         = `git ls-files -z`.split("\x0")
   spec.require_paths = ['lib']
 
-  spec.required_ruby_version = '~> 2.1'
+  spec.required_ruby_version = ['>= 2.1', '< 4']
 
   spec.add_development_dependency 'bundler', ['>= 1.5', '< 3']
   spec.add_development_dependency 'rake'
diff --git a/gemfiles/rails_6.x_active_admin_2.x.gemfile b/gemfiles/rails_6.x_active_admin_2.x.gemfile
new file mode 100644
index 0000000..a10ce61
--- /dev/null
+++ b/gemfiles/rails_6.x_active_admin_2.x.gemfile
@@ -0,0 +1,9 @@
+# This file was generated by Appraisal
+
+source "https://rubygems.org"
+
+gem "sass-rails"
+gem "rails", "~> 6.1"
+gem "activeadmin", "~> 2.0"
+
+gemspec path: "../"