diff --git a/doorkeeper-openid_connect.gemspec b/doorkeeper-openid_connect.gemspec
index 98bfe48..5a440ce 100644
--- a/doorkeeper-openid_connect.gemspec
+++ b/doorkeeper-openid_connect.gemspec
@@ -23,7 +23,7 @@ Gem::Specification.new do |spec|
   spec.add_runtime_dependency 'json-jwt', '~> 1.6'
 
   spec.add_development_dependency 'rspec-rails'
-  spec.add_development_dependency 'factory_girl'
+  spec.add_development_dependency 'factory_bot'
   spec.add_development_dependency 'sqlite3'
   spec.add_development_dependency 'pry-byebug'
   spec.add_development_dependency 'conventional-changelog', '~> 1.2'
diff --git a/spec/factories.rb b/spec/factories.rb
index 94da6fe..43c9344 100644
--- a/spec/factories.rb
+++ b/spec/factories.rb
@@ -1,29 +1,29 @@
-FactoryGirl.define do
+FactoryBot.define do
   factory :access_grant, class: Doorkeeper::AccessGrant do
     resource_owner_id { create(:user).id }
     application
-    redirect_uri 'https://app.com/callback'
-    expires_in 100
-    scopes 'public write'
+    redirect_uri { 'https://app.com/callback' }
+    expires_in { 100 }
+    scopes { 'public write' }
   end
 
   factory :access_token, class: Doorkeeper::AccessToken do
     resource_owner_id { create(:user).id }
     application
-    expires_in 2.hours
+    expires_in { 2.hours }
 
     factory :clientless_access_token do
-      application nil
+      application { nil }
     end
   end
 
   factory :application, class: Doorkeeper::Application do
     sequence(:name) { |n| "Application #{n}" }
-    redirect_uri 'https://app.com/callback'
+    redirect_uri { 'https://app.com/callback' }
   end
 
   factory :user do
-    current_sign_in_at Time.at(23)
+    current_sign_in_at { Time.at(23) }
   end
 
   factory :openid_request, class: Doorkeeper::OpenidConnect::Request do
diff --git a/spec/lib/oauth/id_token_request_spec.rb b/spec/lib/oauth/id_token_request_spec.rb
index 1d56ba7..796cd2e 100644
--- a/spec/lib/oauth/id_token_request_spec.rb
+++ b/spec/lib/oauth/id_token_request_spec.rb
@@ -58,8 +58,8 @@
 
     it 'creates a new token if scopes do not match' do
       allow(Doorkeeper.configuration).to receive(:reuse_access_token).and_return(true)
-      FactoryGirl.create(:access_token, application_id: pre_auth.client.id,
-                         resource_owner_id: owner.id, scopes: '')
+      create(:access_token, application_id: pre_auth.client.id,
+             resource_owner_id: owner.id, scopes: '')
       expect do
         subject.authorize
       end.to change { Doorkeeper::AccessToken.count }.by(1)
@@ -70,8 +70,8 @@
       allow(application.scopes).to receive(:has_scopes?).and_return(true)
       allow(application.scopes).to receive(:all?).and_return(true)
 
-      FactoryGirl.create(:access_token, application_id: pre_auth.client.id,
-                         resource_owner_id: owner.id, scopes: 'public')
+      create(:access_token, application_id: pre_auth.client.id,
+             resource_owner_id: owner.id, scopes: 'public')
 
       expect { subject.authorize }.not_to change { Doorkeeper::AccessToken.count }
     end
diff --git a/spec/rails_helper.rb b/spec/rails_helper.rb
index 5196f07..590ac47 100644
--- a/spec/rails_helper.rb
+++ b/spec/rails_helper.rb
@@ -31,8 +31,8 @@
 
 require_relative 'support/doorkeeper_configuration.rb'
 
-require 'factory_girl'
-FactoryGirl.find_definitions
+require 'factory_bot'
+FactoryBot.find_definitions
 
 RSpec.configure do |config|
   # Remove this line if you're not using ActiveRecord or ActiveRecord fixtures
@@ -48,7 +48,7 @@
   # arbitrary gems may also be filtered via:
   # config.filter_gems_from_backtrace("gem name")
 
-  config.include FactoryGirl::Syntax::Methods
+  config.include FactoryBot::Syntax::Methods
 
   # Reinitialize configuration after each example
   config.after :each do