diff --git a/core/tests/Drupal/TestSite/Commands/TestSiteTearDownCommand.php b/core/tests/Drupal/TestSite/Commands/TestSiteTearDownCommand.php
index e0019a047f..0b7b3afcaa 100644
--- a/core/tests/Drupal/TestSite/Commands/TestSiteTearDownCommand.php
+++ b/core/tests/Drupal/TestSite/Commands/TestSiteTearDownCommand.php
@@ -102,7 +102,7 @@ protected function tearDown(TestDatabase $test_database, $db_url) {
     array_walk($tables, [$schema, 'dropTable']);
 
     // Delete test site directory.
-    $this->fileUnmanagedDeleteRecursive($test_database->getTestSitePath(), [BrowserTestBase::class, 'filePreDeleteCallback']);
+    $this->fileUnmanagedDeleteRecursive($root . DIRECTORY_SEPARATOR . $test_database->getTestSitePath(), [BrowserTestBase::class, 'filePreDeleteCallback']);
   }
 
   /**