diff --git a/src/Symfony/Bridge/Twig/Command/DebugCommand.php b/src/Symfony/Bridge/Twig/Command/DebugCommand.php
index 887f81b1f4211..d4c78210114d7 100644
--- a/src/Symfony/Bridge/Twig/Command/DebugCommand.php
+++ b/src/Symfony/Bridge/Twig/Command/DebugCommand.php
@@ -12,6 +12,8 @@
 namespace Symfony\Bridge\Twig\Command;
 
 use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Completion\CompletionInput;
+use Symfony\Component\Console\Completion\CompletionSuggestions;
 use Symfony\Component\Console\Exception\InvalidArgumentException;
 use Symfony\Component\Console\Formatter\OutputFormatter;
 use Symfony\Component\Console\Input\InputArgument;
@@ -110,6 +112,17 @@ protected function execute(InputInterface $input, OutputInterface $output)
         return 0;
     }
 
+    public function complete(CompletionInput $input, CompletionSuggestions $suggestions): void
+    {
+        if ($input->mustSuggestArgumentValuesFor('name')) {
+            $suggestions->suggestValues(array_keys($this->getLoaderPaths()));
+        }
+
+        if ($input->mustSuggestOptionValuesFor('format')) {
+            $suggestions->suggestValues(['text', 'json']);
+        }
+    }
+
     private function displayPathsText(SymfonyStyle $io, string $name)
     {
         $file = new \ArrayIterator($this->findTemplateFiles($name));
diff --git a/src/Symfony/Bridge/Twig/Tests/Command/DebugCommandTest.php b/src/Symfony/Bridge/Twig/Tests/Command/DebugCommandTest.php
index 327763b8f28ec..2488a27677af9 100644
--- a/src/Symfony/Bridge/Twig/Tests/Command/DebugCommandTest.php
+++ b/src/Symfony/Bridge/Twig/Tests/Command/DebugCommandTest.php
@@ -15,6 +15,7 @@
 use Symfony\Bridge\Twig\Command\DebugCommand;
 use Symfony\Component\Console\Application;
 use Symfony\Component\Console\Exception\InvalidArgumentException;
+use Symfony\Component\Console\Tester\CommandCompletionTester;
 use Symfony\Component\Console\Tester\CommandTester;
 use Twig\Environment;
 use Twig\Loader\ChainLoader;
@@ -293,6 +294,33 @@ public function testWithFilter()
         $this->assertNotSame($display1, $display2);
     }
 
+    /**
+     * @dataProvider provideCompletionSuggestions
+     */
+    public function testComplete(array $input, array $expectedSuggestions)
+    {
+        if (!class_exists(CommandCompletionTester::class)) {
+            $this->markTestSkipped('Test command completion requires symfony/console 5.4+.');
+        }
+
+        $projectDir = \dirname(__DIR__).\DIRECTORY_SEPARATOR.'Fixtures';
+        $loader = new FilesystemLoader([], $projectDir);
+        $environment = new Environment($loader);
+
+        $application = new Application();
+        $application->add(new DebugCommand($environment, $projectDir, [], null, null));
+
+        $tester = new CommandCompletionTester($application->find('debug:twig'));
+        $suggestions = $tester->complete($input, 2);
+        $this->assertSame($expectedSuggestions, $suggestions);
+    }
+
+    public function provideCompletionSuggestions(): iterable
+    {
+        yield 'name' => [['email'], []];
+        yield 'option --format' => [['--format', ''], ['text', 'json']];
+    }
+
     private function createCommandTester(array $paths = [], array $bundleMetadata = [], string $defaultPath = null, bool $useChainLoader = false, array $globals = []): CommandTester
     {
         $projectDir = \dirname(__DIR__).\DIRECTORY_SEPARATOR.'Fixtures';