diff --git a/actionpack/CHANGELOG.md b/actionpack/CHANGELOG.md
index 0d24dbe0d0279..557832332e4e1 100644
--- a/actionpack/CHANGELOG.md
+++ b/actionpack/CHANGELOG.md
@@ -1,3 +1,7 @@
+*   Remove deprecated `ActionDispatch::SystemTestCase#host!`.
+
+    *Rafael Mendonça França*
+
 *   Remove deprecated `Rails.config.action_dispatch.hosts_response_app`.
 
     *Rafael Mendonça França*
diff --git a/actionpack/lib/action_dispatch/system_testing/test_helpers/setup_and_teardown.rb b/actionpack/lib/action_dispatch/system_testing/test_helpers/setup_and_teardown.rb
index 30dc21ebb92bf..68d99a2a992c3 100644
--- a/actionpack/lib/action_dispatch/system_testing/test_helpers/setup_and_teardown.rb
+++ b/actionpack/lib/action_dispatch/system_testing/test_helpers/setup_and_teardown.rb
@@ -4,14 +4,6 @@ module ActionDispatch
   module SystemTesting
     module TestHelpers
       module SetupAndTeardown # :nodoc:
-        def host!(host)
-          ActiveSupport::Deprecation.warn \
-            "ActionDispatch::SystemTestCase#host! is deprecated with no replacement. " \
-            "Set Capybara.app_host directly or rely on Capybara's default host."
-
-          Capybara.app_host = host
-        end
-
         def before_teardown
           take_failed_screenshot
         ensure
diff --git a/actionpack/test/dispatch/system_testing/system_test_case_test.rb b/actionpack/test/dispatch/system_testing/system_test_case_test.rb
index 8450a73e4aa51..855fb89e671e4 100644
--- a/actionpack/test/dispatch/system_testing/system_test_case_test.rb
+++ b/actionpack/test/dispatch/system_testing/system_test_case_test.rb
@@ -42,17 +42,3 @@ class SetDriverToSeleniumHeadlessFirefoxTest < DrivenBySeleniumWithHeadlessFiref
     assert_equal :selenium, Capybara.current_driver
   end
 end
-
-class SetHostTest < DrivenByRackTest
-  teardown do
-    Capybara.app_host = nil
-  end
-
-  test "overrides host" do
-    assert_deprecated do
-      host! "http://example.com"
-    end
-
-    assert_equal "http://example.com", Capybara.app_host
-  end
-end
diff --git a/guides/source/7_0_release_notes.md b/guides/source/7_0_release_notes.md
index d68379c7b35f0..489ad0507dfe9 100644
--- a/guides/source/7_0_release_notes.md
+++ b/guides/source/7_0_release_notes.md
@@ -56,6 +56,8 @@ Please refer to the [Changelog][action-pack] for detailed changes.
 
 *   Remove deprecated `Rails.config.action_dispatch.hosts_response_app`.
 
+*   Remove deprecated `ActionDispatch::SystemTestCase#host!`.
+
 ### Deprecations
 
 ### Notable changes