diff --git a/.github/workflows/run-tests.yml b/.github/workflows/run-tests.yml
index ec52cbc..8da058a 100644
--- a/.github/workflows/run-tests.yml
+++ b/.github/workflows/run-tests.yml
@@ -14,16 +14,22 @@ jobs:
       matrix:
         os: [ubuntu-latest]
         php: [8.0, 8.1, 8.2, 8.3]
-        laravel: [10.*, 9.*]
-        stability: [prefer-lowest, prefer-stable]
+        laravel: [11.*, 10.*, 9.*]
+        stability: [prefer-stable]
         include:
           - laravel: 9.*
             testbench: 7.*
           - laravel: 10.*
             testbench: 8.*
+          - laravel: 11.*
+            testbench: 9.*
         exclude:
           - laravel: 10.*
             php: 8.0
+          - laravel: 11.*
+            php: 8.0
+          - laravel: 11.*
+            php: 8.1
 
     name: P${{ matrix.php }} - L${{ matrix.laravel }} - ${{ matrix.stability }} - ${{ matrix.os }}
 
diff --git a/composer.json b/composer.json
index ac49a8a..367e49e 100644
--- a/composer.json
+++ b/composer.json
@@ -21,16 +21,16 @@
     "require": {
         "php": "^8.0",
         "spatie/laravel-package-tools": "^1.14.0",
-        "illuminate/contracts": "^9.28|^10.0"
+        "illuminate/contracts": "^9.28|^10.0|^11.0"
     },
     "require-dev": {
         "laravel/pint": "^1.4",
-        "nunomaduro/collision": "^6.0|^7.0",
-        "nunomaduro/larastan": "^2.0",
-        "orchestra/testbench": "^7.7|^8.0",
-        "pestphp/pest": "^1.22|^2.0",
+        "nunomaduro/collision": "^6.0|^7.0|^8.0",
+        "larastan/larastan": "^2.0",
+        "orchestra/testbench": "^7.7|^8.0|^9.0",
+        "pestphp/pest": "^1.22|^2.0|^3.0",
         "phpstan/extension-installer": "^1.2",
-        "phpunit/phpunit": "^9.5.27|^10.0"
+        "phpunit/phpunit": "^9.5.27|^10.0|^11.0"
     },
     "autoload": {
         "psr-4": {
diff --git a/src/Commands/BreezejpCommand.php b/src/Commands/BreezejpCommand.php
index 94d4be7..9c63aac 100644
--- a/src/Commands/BreezejpCommand.php
+++ b/src/Commands/BreezejpCommand.php
@@ -25,17 +25,55 @@ public function handle(): int
         (new Filesystem)->ensureDirectoryExists(lang_path());
         (new Filesystem)->copyDirectory(__DIR__.'/../../stubs/lang/', lang_path());
 
-        $this->info('config/app.phpのlocaleをjaにします');
+        $envfile = file_get_contents(base_path('.env'));
+
+        if (strpos($envfile, 'APP_FAKER_LOCALE') == false) {
+            $this->info('config/app.phpのlocaleをjaにします');
+            // Read the contents of the file into a string
+            $configfile = file_get_contents(base_path('config/app.php'));
+
+            // Modify the contents of the string
+            $configfile = str_replace("'locale' => 'en'", "'locale' => 'ja'", $configfile);
+            $configfile = str_replace("'faker_locale' => 'en_US'", "'faker_locale' => 'ja_JP'", $configfile);
+            $configfile = str_replace("'timezone' => 'UTC'", "'timezone' => 'Asia/Tokyo'", $configfile);
+
+            // Save the modified contents back to the file
+            file_put_contents(base_path('config/app.php'), $configfile);
+
+            if ($this->confirm('GitHubリポジトリにスターの御協力をお願いします🙏', true)) {
+                $repoUrl = 'https://github.com/askdkc/breezejp';
+
+                if (PHP_OS_FAMILY == 'Darwin') {
+                    exec("open {$repoUrl}");
+                }
+                if (PHP_OS_FAMILY == 'Windows') {
+                    exec("start {$repoUrl}");
+                }
+                if (PHP_OS_FAMILY == 'Linux') {
+                    exec("xdg-open {$repoUrl}");
+                }
+
+                $this->line('Thank you! / ありがとう💓');
+            }
+
+            $this->info('日本語ファイルのインストールが完了しました!');
+
+            return self::SUCCESS;
+
+        }
+
+        // For Laravel 11 and above
+        $this->info('.envのAPP_LOCALEやTAPP_IMEZONEを日本にします');
         // Read the contents of the file into a string
-        $configfile = file_get_contents(base_path('config/app.php'));
+        $configfile = file_get_contents(base_path('.env'));
 
         // Modify the contents of the string
-        $configfile = str_replace("'locale' => 'en'", "'locale' => 'ja'", $configfile);
-        $configfile = str_replace("'faker_locale' => 'en_US'", "'faker_locale' => 'ja_JP'", $configfile);
-        $configfile = str_replace("'timezone' => 'UTC'", "'timezone' => 'Asia/Tokyo'", $configfile);
+        $configfile = str_replace('APP_LOCALE=en', 'APP_LOCALE=ja', $configfile);
+        $configfile = str_replace('APP_FAKER_LOCALE=en_US', 'APP_FAKER_LOCALE=ja_JP', $configfile);
+        $configfile = str_replace('APP_TIMEZONE=UTC', 'APP_TIMEZONE=Asia/Tokyo', $configfile);
 
         // Save the modified contents back to the file
-        file_put_contents(base_path('config/app.php'), $configfile);
+        file_put_contents(base_path('.env'), $configfile);
 
         if ($this->confirm('GitHubリポジトリにスターの御協力をお願いします🙏', true)) {
             $repoUrl = 'https://github.com/askdkc/breezejp';
@@ -56,5 +94,6 @@ public function handle(): int
         $this->info('日本語ファイルのインストールが完了しました!');
 
         return self::SUCCESS;
+
     }
 }
diff --git a/tests/CommandTest.php b/tests/CommandTest.php
index 1c0c284..09d7bfd 100644
--- a/tests/CommandTest.php
+++ b/tests/CommandTest.php
@@ -1,5 +1,9 @@
 <?php
 
+test('.env file exists', function () {
+    $this->assertFileExists(base_path('.env'));
+});
+
 test('breezejp command successfully run and see all the published files', closure: function () {
     $this->artisan('breezejp')
         ->expectsOutput('Laravel Breeze用に日本語翻訳ファイルを準備します')
@@ -21,10 +25,17 @@
         ->expectsOutput('日本語ファイルのインストールが完了しました!')
         ->assertExitCode(0);
 
-    $configfile = file_get_contents(base_path('config/app.php'));
-    $this->assertStringContainsString("'locale' => 'ja'", $configfile);
-    $this->assertStringContainsString("'faker_locale' => 'ja_JP'", $configfile);
-    $this->assertStringContainsString("'timezone' => 'Asia/Tokyo'", $configfile);
+    if ((int) substr(Illuminate\Foundation\Application::VERSION, 0, 2) < 11) {
+        $configfile = file_get_contents(base_path('config/app.php'));
+        $this->assertStringContainsString("'locale' => 'ja'", $configfile);
+        $this->assertStringContainsString("'faker_locale' => 'ja_JP'", $configfile);
+        $this->assertStringContainsString("'timezone' => 'Asia/Tokyo'", $configfile);
+    } else { // For Laravel 11 and above
+        $configfile = file_get_contents(base_path('.env'));
+        $this->assertStringContainsString('APP_LOCALE=ja', $configfile);
+        $this->assertStringContainsString('APP_FAKER_LOCALE=ja_JP', $configfile);
+        $this->assertStringContainsString('APP_TIMEZONE=Asia/Tokyo', $configfile);
+    }
 });
 
 test('breezejp command successfully update config/app.php timezone to Asia/Tokyo', function () {
@@ -34,6 +45,11 @@
         ->expectsOutput('日本語ファイルのインストールが完了しました!')
         ->assertExitCode(0);
 
-    $configfile = file_get_contents(base_path('config/app.php'));
-    $this->assertStringContainsString("'timezone' => 'Asia/Tokyo'", $configfile);
+    if ((int) substr(Illuminate\Foundation\Application::VERSION, 0, 2) < 11) {
+        $configfile = file_get_contents(base_path('config/app.php'));
+        $this->assertStringContainsString("'timezone' => 'Asia/Tokyo'", $configfile);
+    } else { // For Laravel 11 and above
+        $configfile = file_get_contents(base_path('.env'));
+        $this->assertStringContainsString('APP_TIMEZONE=Asia/Tokyo', $configfile);
+    }
 });
diff --git a/tests/TestCase.php b/tests/TestCase.php
index 0ff1962..08ab769 100644
--- a/tests/TestCase.php
+++ b/tests/TestCase.php
@@ -12,6 +12,8 @@ protected function setUp(): void
     {
         parent::setUp();
 
+        copy(__DIR__.'/../vendor/orchestra/testbench-core/laravel/.env.example', __DIR__.'/../vendor/orchestra/testbench-core/laravel/.env');
+
         // テスト用のファイルが残ってたら消す(web.php)
         if (is_file(__DIR__.'/../vendor/orchestra/testbench-core/laravel/routes/web.php')) {
             unlink(__DIR__.'/../vendor/orchestra/testbench-core/laravel/routes/web.php');