diff --git a/src/Check/Mailer/SymfonyMailerSmtpConnectionCheck.php b/src/Check/Mailer/SymfonyMailerSmtpConnectionCheck.php
index a4221f1..374861b 100644
--- a/src/Check/Mailer/SymfonyMailerSmtpConnectionCheck.php
+++ b/src/Check/Mailer/SymfonyMailerSmtpConnectionCheck.php
@@ -17,6 +17,7 @@
 use FiveLab\Component\Diagnostic\Result\Failure;
 use FiveLab\Component\Diagnostic\Result\Result;
 use FiveLab\Component\Diagnostic\Result\Success;
+use FiveLab\Component\Diagnostic\Util\HttpSecurityEncoder;
 use Symfony\Component\Mailer\Exception\TransportException;
 use Symfony\Component\Mailer\Transport;
 
@@ -28,11 +29,16 @@ class SymfonyMailerSmtpConnectionCheck implements CheckInterface
     /**
      * Constructor.
      *
-     * @param string     $dsn
-     * @param array<int> $codes
+     * @param string              $dsn
+     * @param array<int>          $codes
+     * @param HttpSecurityEncoder $securityEncoder
      */
-    public function __construct(private readonly string $dsn, private readonly array $codes = [220, 250])
-    {
+    public function __construct(
+        private readonly string      $dsn,
+        private readonly array       $codes = [220, 250],
+        private ?HttpSecurityEncoder $securityEncoder = null
+    ) {
+        $this->securityEncoder = $this->securityEncoder ?: new HttpSecurityEncoder();
     }
 
     /**
@@ -84,7 +90,7 @@ public function check(): Result
     public function getExtraParameters(): array
     {
         return [
-            'dsn' => $this->dsn,
+            'dsn' => $this->securityEncoder->encodeUri($this->dsn),
         ];
     }
 }
diff --git a/tests/Check/Mailer/SymfonyMailerSmtpConnectionCheckTest.php b/tests/Check/Mailer/SymfonyMailerSmtpConnectionCheckTest.php
index 14be629..bfae8a5 100644
--- a/tests/Check/Mailer/SymfonyMailerSmtpConnectionCheckTest.php
+++ b/tests/Check/Mailer/SymfonyMailerSmtpConnectionCheckTest.php
@@ -61,4 +61,14 @@ public function shouldSuccessGetExtra(): void
             'dsn' => 'smtp://foo-bar:1025?username=some',
         ], $check->getExtraParameters());
     }
+
+    #[Test]
+    public function shouldSuccessGetExtraWithHidePassword(): void
+    {
+        $check = new SymfonyMailerSmtpConnectionCheck('smtp://user:pass@foo-bar:1025?username=some');
+
+        self::assertEquals([
+            'dsn' => 'smtp://user:***@foo-bar:1025?username=some',
+        ], $check->getExtraParameters());
+    }
 }