diff --git a/core/modules/config_translation/migration_templates/d6_i18n_system_site.yml b/core/modules/config_translation/migration_templates/d6_i18n_system_site.yml
new file mode 100644
index 00000000000..9c9337c42fa
--- /dev/null
+++ b/core/modules/config_translation/migration_templates/d6_i18n_system_site.yml
@@ -0,0 +1,38 @@
+id: d6_i18n_system_site
+label: Site configuration
+migration_tags:
+  - Drupal 6
+source:
+  plugin: i18n_variable
+  constants:
+    slash: '/'
+  variables:
+    - site_name
+    - site_mail
+    - site_slogan
+    - site_frontpage
+    - site_403
+    - site_404
+process:
+  langcode: language
+  name: site_name
+  mail: site_mail
+  slogan: site_slogan
+  'page/front':
+    plugin: concat
+    source:
+      - constants/slash
+      - site_frontpage
+  'page/403':
+    plugin: concat
+    source:
+      - constants/slash
+      - site_403
+  'page/404':
+    plugin: concat
+    source:
+      - constants/slash
+      - site_404
+destination:
+  plugin: config
+  config_name: system.site
diff --git a/core/modules/config_translation/tests/src/Kernel/Migrate/d6/MigrateI18nSystemSiteTest.php b/core/modules/config_translation/tests/src/Kernel/Migrate/d6/MigrateI18nSystemSiteTest.php
new file mode 100644
index 00000000000..770b33ca114
--- /dev/null
+++ b/core/modules/config_translation/tests/src/Kernel/Migrate/d6/MigrateI18nSystemSiteTest.php
@@ -0,0 +1,47 @@
+<?php
+
+namespace Drupal\Tests\config_translation\Kernel\Migrate\d6;
+
+use Drupal\Tests\migrate_drupal\Kernel\d6\MigrateDrupal6TestBase;
+
+/**
+ * Upgrade i18n_strings site variables to system.*.yml.
+ *
+ * @group migrate_drupal_6
+ */
+class MigrateI18nSystemSiteTest extends MigrateDrupal6TestBase {
+
+  public static $modules = ['language', 'config_translation'];
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+    $this->executeMigration('d6_i18n_system_site');
+  }
+
+  /**
+   * Tests migration of system (site) variables to system.site.yml.
+   */
+  public function testSystemSite() {
+    $config_translation = \Drupal::service('language_manager')->getLanguageConfigOverride('fr', 'system.site');
+    $this->assertIdentical('fr site name', $config_translation->get('name'));
+    $this->assertIdentical('fr_site_mail@example.com', $config_translation->get('mail'));
+    $this->assertIdentical('fr Migrate rocks', $config_translation->get('slogan'));
+    $this->assertIdentical('/fr-user', $config_translation->get('page.403'));
+    $this->assertIdentical('/fr-page-not-found', $config_translation->get('page.404'));
+    $this->assertIdentical('/node', $config_translation->get('page.front'));
+    $this->assertIdentical(NULL, $config_translation->get('admin_compact_mode'));
+
+    $config_translation = \Drupal::service('language_manager')->getLanguageConfigOverride('zu', 'system.site');
+    $this->assertIdentical('zu - site_name', $config_translation->get('name'));
+    $this->assertIdentical('site_mail@example.com', $config_translation->get('mail'));
+    $this->assertIdentical('Migrate rocks', $config_translation->get('slogan'));
+    $this->assertIdentical('/zu-user', $config_translation->get('page.403'));
+    $this->assertIdentical('/zu-page-not-found', $config_translation->get('page.404'));
+    $this->assertIdentical('/node', $config_translation->get('page.front'));
+    $this->assertIdentical(NULL, $config_translation->get('admin_compact_mode'));
+  }
+
+}