diff --git a/TASK_CHECKUP.md b/TASK_CHECKUP.md
index f0ad16e..87d799d 100644
--- a/TASK_CHECKUP.md
+++ b/TASK_CHECKUP.md
@@ -28,7 +28,7 @@
 - [ ] Admin : liste de toutes les commandes avec filtres
 - [ ] Admin : pouvoir suspendre un organisateur
 - [ ] Admin : pouvoir modifier l'offre/commission d'un orga existant (déjà fait partiellement)
-  - [ ] Admin : logs des actions importantes (audit trail)
+- [x] Admin : logs des actions importantes (audit trail: commande, paiement, annulation, remboursement)
 
 ### UX & Pages
 - [x] Page /tarifs : détailler les 3 offres (free/basic/custom) avec commissions et exemples
diff --git a/migrations/Version20260322120000.php b/migrations/Version20260322120000.php
new file mode 100644
index 0000000..8285799
--- /dev/null
+++ b/migrations/Version20260322120000.php
@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DoctrineMigrations;
+
+use Doctrine\DBAL\Schema\Schema;
+use Doctrine\Migrations\AbstractMigration;
+
+final class Version20260322120000 extends AbstractMigration
+{
+    public function getDescription(): string
+    {
+        return 'Create audit_log table';
+    }
+
+    public function up(Schema $schema): void
+    {
+        $this->addSql('CREATE TABLE audit_log (id INT GENERATED BY DEFAULT AS IDENTITY NOT NULL, action VARCHAR(50) NOT NULL, entity_type VARCHAR(255) NOT NULL, entity_id INT DEFAULT NULL, data JSON NOT NULL, performed_by VARCHAR(255) DEFAULT NULL, ip_address VARCHAR(45) DEFAULT NULL, created_at TIMESTAMP(0) WITHOUT TIME ZONE NOT NULL, PRIMARY KEY(id))');
+        $this->addSql('CREATE INDEX IDX_AUDIT_ACTION ON audit_log (action)');
+        $this->addSql('CREATE INDEX IDX_AUDIT_CREATED ON audit_log (created_at)');
+    }
+
+    public function down(Schema $schema): void
+    {
+        $this->addSql('DROP TABLE audit_log');
+    }
+}
diff --git a/phpstan.neon b/phpstan.neon
index 9dcbdc6..417c2c3 100644
--- a/phpstan.neon
+++ b/phpstan.neon
@@ -6,7 +6,7 @@ parameters:
         - src/Kernel.php
     ignoreErrors:
         -
-            message: '#Property App\\Entity\\(EmailTracking|MessengerLog|User|Payout|Event|Category|Billet|BilletDesign|BilletBuyer|BilletBuyerItem|BilletOrder|OrganizerInvitation)::\$id .* never assigned#'
+            message: '#Property App\\Entity\\(EmailTracking|MessengerLog|User|Payout|Event|Category|Billet|BilletDesign|BilletBuyer|BilletBuyerItem|BilletOrder|OrganizerInvitation|AuditLog)::\$id .* never assigned#'
             reportUnmatched: false
             paths:
                 - src/Entity/EmailTracking.php
@@ -21,6 +21,7 @@ parameters:
                 - src/Entity/BilletBuyerItem.php
                 - src/Entity/BilletOrder.php
                 - src/Entity/OrganizerInvitation.php
+                - src/Entity/AuditLog.php
         -
             message: '#Parameter \#1 \$params of method Stripe\\Service\\.*::create\(\) expects#'
             path: src/Controller/OrderController.php
diff --git a/src/Controller/AccountController.php b/src/Controller/AccountController.php
index e631c3d..dad8a8f 100644
--- a/src/Controller/AccountController.php
+++ b/src/Controller/AccountController.php
@@ -11,6 +11,7 @@ use App\Entity\Category;
 use App\Entity\Event;
 use App\Entity\Payout;
 use App\Entity\User;
+use App\Service\AuditService;
 use App\Service\BilletOrderService;
 use App\Service\EventIndexService;
 use App\Service\MailerService;
@@ -817,7 +818,7 @@ class AccountController extends AbstractController
     }
 
     #[Route('/mon-compte/evenement/{id}/commande/{orderId}/annuler', name: 'app_account_event_cancel_order', methods: ['POST'])]
-    public function cancelOrder(Event $event, int $orderId, EntityManagerInterface $em): Response
+    public function cancelOrder(Event $event, int $orderId, EntityManagerInterface $em, AuditService $audit): Response
     {
         $this->denyAccessUnlessGranted('ROLE_ORGANIZER');
 
@@ -841,6 +842,11 @@ class AccountController extends AbstractController
 
         $em->flush();
 
+        $audit->log('order_cancelled', 'BilletBuyer', $order->getId(), [
+            'orderNumber' => $order->getOrderNumber(),
+            'event' => $event->getTitle(),
+        ]);
+
         $this->addFlash('success', 'Commande '.$order->getOrderNumber().' annulee.');
 
         return $this->redirectToRoute('app_account_edit_event', ['id' => $event->getId(), 'tab' => 'stats']);
@@ -850,7 +856,7 @@ class AccountController extends AbstractController
      * @codeCoverageIgnore Requires live Stripe API
      */
     #[Route('/mon-compte/evenement/{id}/commande/{orderId}/rembourser', name: 'app_account_event_refund_order', methods: ['POST'])]
-    public function refundOrder(Event $event, int $orderId, EntityManagerInterface $em, StripeService $stripeService): Response
+    public function refundOrder(Event $event, int $orderId, EntityManagerInterface $em, StripeService $stripeService, AuditService $audit): Response
     {
         $this->denyAccessUnlessGranted('ROLE_ORGANIZER');
 
@@ -884,6 +890,12 @@ class AccountController extends AbstractController
 
         $em->flush();
 
+        $audit->log('order_refunded', 'BilletBuyer', $order->getId(), [
+            'orderNumber' => $order->getOrderNumber(),
+            'event' => $event->getTitle(),
+            'totalHT' => $order->getTotalHTDecimal(),
+        ]);
+
         $this->addFlash('success', 'Commande '.$order->getOrderNumber().' remboursee.');
 
         return $this->redirectToRoute('app_account_edit_event', ['id' => $event->getId(), 'tab' => 'stats']);
diff --git a/src/Controller/AdminController.php b/src/Controller/AdminController.php
index 18e3de8..3e47d9c 100644
--- a/src/Controller/AdminController.php
+++ b/src/Controller/AdminController.php
@@ -2,6 +2,7 @@
 
 namespace App\Controller;
 
+use App\Entity\AuditLog;
 use App\Entity\OrganizerInvitation;
 use App\Entity\User;
 use App\Service\MailerService;
@@ -443,6 +444,17 @@ class AdminController extends AbstractController
         ]);
     }
 
+    #[Route('/logs', name: 'app_admin_logs', methods: ['GET'])]
+    public function logs(Request $request, EntityManagerInterface $em, PaginatorInterface $paginator): Response
+    {
+        $logs = $em->getRepository(AuditLog::class)->findBy([], ['createdAt' => 'DESC']);
+        $paginatedLogs = $paginator->paginate($logs, $request->query->getInt('page', 1), 30);
+
+        return $this->render('admin/logs.html.twig', [
+            'logs' => $paginatedLogs,
+        ]);
+    }
+
     #[Route('/organisateurs/inviter', name: 'app_admin_invite_organizer', methods: ['GET', 'POST'])]
     public function inviteOrganizer(Request $request, EntityManagerInterface $em, MailerService $mailerService): Response
     {
diff --git a/src/Controller/OrderController.php b/src/Controller/OrderController.php
index 0b53f65..b14460e 100644
--- a/src/Controller/OrderController.php
+++ b/src/Controller/OrderController.php
@@ -8,6 +8,7 @@ use App\Entity\BilletBuyerItem;
 use App\Entity\BilletOrder;
 use App\Entity\Event;
 use App\Entity\User;
+use App\Service\AuditService;
 use App\Service\BilletOrderService;
 use App\Service\InvoiceService;
 use App\Service\StripeService;
@@ -22,7 +23,7 @@ class OrderController extends AbstractController
     private const REF_PATTERN = 'ETICKET-[A-Z0-9]{4}-[A-Z0-9]{4}-[A-Z0-9]{4}';
 
     #[Route('/evenement/{id}/commander', name: 'app_order_create', requirements: ['id' => '\d+'], methods: ['POST'])]
-    public function create(int $id, Request $request, EntityManagerInterface $em): Response
+    public function create(int $id, Request $request, EntityManagerInterface $em, AuditService $audit): Response
     {
         $event = $em->getRepository(Event::class)->find($id);
         if (!$event || !$event->isOnline()) {
@@ -67,6 +68,12 @@ class OrderController extends AbstractController
         $em->persist($order);
         $em->flush();
 
+        $audit->log('order_created', 'BilletBuyer', $order->getId(), [
+            'orderNumber' => $order->getOrderNumber(),
+            'event' => $event->getTitle(),
+            'totalHT' => $order->getTotalHTDecimal(),
+        ]);
+
         $redirect = $user
             ? $this->generateUrl('app_order_payment', ['id' => $order->getId()])
             : $this->generateUrl('app_order_guest', ['id' => $order->getId()]);
@@ -185,7 +192,7 @@ class OrderController extends AbstractController
     }
 
     #[Route('/commande/{id}/confirmation', name: 'app_order_success', requirements: ['id' => '\d+'], methods: ['GET'])]
-    public function success(int $id, Request $request, EntityManagerInterface $em, BilletOrderService $billetOrderService, StripeService $stripeService): Response
+    public function success(int $id, Request $request, EntityManagerInterface $em, BilletOrderService $billetOrderService, StripeService $stripeService, AuditService $audit): Response
     {
         $order = $em->getRepository(BilletBuyer::class)->find($id);
         if (!$order) {
@@ -198,6 +205,10 @@ class OrderController extends AbstractController
         if ('succeeded' === $redirectStatus && BilletBuyer::STATUS_PENDING === $order->getStatus()) {
             $this->savePaymentDetails($order, $paymentIntentId, $stripeService, $em);
             $billetOrderService->generateOrderTickets($order);
+            $audit->log('order_paid', 'BilletBuyer', $order->getId(), [
+                'orderNumber' => $order->getOrderNumber(),
+                'totalHT' => $order->getTotalHTDecimal(),
+            ]);
             $billetOrderService->generateAndSendTickets($order);
         }
 
diff --git a/src/Entity/AuditLog.php b/src/Entity/AuditLog.php
new file mode 100644
index 0000000..40784b3
--- /dev/null
+++ b/src/Entity/AuditLog.php
@@ -0,0 +1,105 @@
+<?php
+
+namespace App\Entity;
+
+use App\Repository\AuditLogRepository;
+use Doctrine\ORM\Mapping as ORM;
+
+#[ORM\Entity(repositoryClass: AuditLogRepository::class)]
+class AuditLog
+{
+    #[ORM\Id]
+    #[ORM\GeneratedValue]
+    #[ORM\Column]
+    private ?int $id = null;
+
+    #[ORM\Column(length: 50)]
+    private string $action;
+
+    #[ORM\Column(length: 255)]
+    private string $entityType;
+
+    #[ORM\Column(nullable: true)]
+    private ?int $entityId = null;
+
+    #[ORM\Column(type: 'json')]
+    private array $data = [];
+
+    #[ORM\Column(length: 255, nullable: true)]
+    private ?string $performedBy = null;
+
+    #[ORM\Column(length: 45, nullable: true)]
+    private ?string $ipAddress = null;
+
+    #[ORM\Column]
+    private \DateTimeImmutable $createdAt;
+
+    public function __construct(string $action, string $entityType, ?int $entityId = null)
+    {
+        $this->action = $action;
+        $this->entityType = $entityType;
+        $this->entityId = $entityId;
+        $this->createdAt = new \DateTimeImmutable();
+    }
+
+    public function getId(): ?int
+    {
+        return $this->id;
+    }
+
+    public function getAction(): string
+    {
+        return $this->action;
+    }
+
+    public function getEntityType(): string
+    {
+        return $this->entityType;
+    }
+
+    public function getEntityId(): ?int
+    {
+        return $this->entityId;
+    }
+
+    public function getData(): array
+    {
+        return $this->data;
+    }
+
+    public function setData(array $data): static
+    {
+        $this->data = $data;
+
+        return $this;
+    }
+
+    public function getPerformedBy(): ?string
+    {
+        return $this->performedBy;
+    }
+
+    public function setPerformedBy(?string $performedBy): static
+    {
+        $this->performedBy = $performedBy;
+
+        return $this;
+    }
+
+    public function getIpAddress(): ?string
+    {
+        return $this->ipAddress;
+    }
+
+    public function setIpAddress(?string $ipAddress): static
+    {
+        $this->ipAddress = $ipAddress;
+
+        return $this;
+    }
+
+    public function getCreatedAt(): \DateTimeImmutable
+    {
+        return $this->createdAt;
+    }
+}
diff --git a/src/Repository/AuditLogRepository.php b/src/Repository/AuditLogRepository.php
new file mode 100644
index 0000000..8f5a971
--- /dev/null
+++ b/src/Repository/AuditLogRepository.php
@@ -0,0 +1,18 @@
+<?php
+
+namespace App\Repository;
+
+use App\Entity\AuditLog;
+use Doctrine\Bundle\DoctrineBundle\Repository\ServiceEntityRepository;
+use Doctrine\Persistence\ManagerRegistry;
+
+/**
+ * @extends ServiceEntityRepository<AuditLog>
+ */
+class AuditLogRepository extends ServiceEntityRepository
+{
+    public function __construct(ManagerRegistry $registry)
+    {
+        parent::__construct($registry, AuditLog::class);
+    }
+}
diff --git a/src/Service/AuditService.php b/src/Service/AuditService.php
new file mode 100644
index 0000000..093c43c
--- /dev/null
+++ b/src/Service/AuditService.php
@@ -0,0 +1,37 @@
+<?php
+
+namespace App\Service;
+
+use App\Entity\AuditLog;
+use Doctrine\ORM\EntityManagerInterface;
+use Symfony\Bundle\SecurityBundle\Security;
+use Symfony\Component\HttpFoundation\RequestStack;
+
+class AuditService
+{
+    public function __construct(
+        private EntityManagerInterface $em,
+        private Security $security,
+        private RequestStack $requestStack,
+    ) {
+    }
+
+    public function log(string $action, string $entityType, ?int $entityId = null, array $data = []): void
+    {
+        $log = new AuditLog($action, $entityType, $entityId);
+        $log->setData($data);
+
+        $user = $this->security->getUser();
+        if ($user) {
+            $log->setPerformedBy($user->getUserIdentifier());
+        }
+
+        $request = $this->requestStack->getCurrentRequest();
+        if ($request) {
+            $log->setIpAddress($request->getClientIp());
+        }
+
+        $this->em->persist($log);
+        $this->em->flush();
+    }
+}
diff --git a/templates/admin/base.html.twig b/templates/admin/base.html.twig
index 9778124..2bf5c64 100644
--- a/templates/admin/base.html.twig
+++ b/templates/admin/base.html.twig
@@ -22,6 +22,7 @@
                     <a href="{{ path('app_admin_buyers') }}" class="px-3 py-1.5 text-xs font-black uppercase tracking-widest transition-all {{ current_route starts with 'app_admin_buyer' ? 'admin-nav-active' : 'hover:bg-gray-100' }}">Acheteurs</a>
                     <a href="{{ path('app_admin_organizers') }}" class="px-3 py-1.5 text-xs font-black uppercase tracking-widest transition-all {{ current_route starts with 'app_admin_organizer' ? 'admin-nav-active' : 'hover:bg-gray-100' }}">Organisateurs</a>
                     <a href="{{ path('app_admin_events') }}" class="px-3 py-1.5 text-xs font-black uppercase tracking-widest transition-all {{ current_route starts with 'app_admin_event' ? 'admin-nav-active' : 'hover:bg-gray-100' }}">Evenements</a>
+                    <a href="{{ path('app_admin_logs') }}" class="px-3 py-1.5 text-xs font-black uppercase tracking-widest transition-all {{ current_route == 'app_admin_logs' ? 'admin-nav-active' : 'hover:bg-gray-100' }}">Logs</a>
                 </nav>
             </div>
             <div class="flex items-center gap-3">
diff --git a/templates/admin/logs.html.twig b/templates/admin/logs.html.twig
new file mode 100644
index 0000000..b591e7a
--- /dev/null
+++ b/templates/admin/logs.html.twig
@@ -0,0 +1,69 @@
+{% extends 'admin/base.html.twig' %}
+
+{% block title %}Logs{% endblock %}
+
+{% block body %}
+<div class="mb-8">
+    <h1 class="text-3xl font-black uppercase tracking-tighter italic heading-page">Audit trail</h1>
+    <p class="font-bold text-gray-500 italic">{{ logs.getTotalItemCount }} action{{ logs.getTotalItemCount > 1 ? 's' : '' }}.</p>
+</div>
+
+<div class="admin-card !p-0">
+    <table class="admin-table">
+        <thead>
+            <tr>
+                <th class="text-[10px] font-black uppercase tracking-widest text-white">Date</th>
+                <th class="text-[10px] font-black uppercase tracking-widest text-white">Action</th>
+                <th class="text-[10px] font-black uppercase tracking-widest text-white">Entite</th>
+                <th class="text-[10px] font-black uppercase tracking-widest text-white">Details</th>
+                <th class="text-[10px] font-black uppercase tracking-widest text-white">Par</th>
+                <th class="text-[10px] font-black uppercase tracking-widest text-white">IP</th>
+            </tr>
+        </thead>
+        <tbody>
+            {% for log in logs %}
+            <tr class="hover:bg-gray-50 transition-all">
+                <td class="text-xs text-gray-500 whitespace-nowrap">{{ log.createdAt|date('d/m/Y H:i:s') }}</td>
+                <td>
+                    {% if log.action == 'order_created' %}
+                        <span class="admin-badge-yellow text-xs font-black uppercase">Commande</span>
+                    {% elseif log.action == 'order_paid' %}
+                        <span class="admin-badge-green text-xs font-black uppercase">Payee</span>
+                    {% elseif log.action == 'order_cancelled' %}
+                        <span class="admin-badge-red text-xs font-black uppercase">Annulee</span>
+                    {% elseif log.action == 'order_refunded' %}
+                        <span class="admin-badge-yellow text-xs font-black uppercase">Remboursee</span>
+                    {% else %}
+                        <span class="admin-badge-indigo text-xs font-black uppercase">{{ log.action }}</span>
+                    {% endif %}
+                </td>
+                <td class="text-xs text-gray-600">{{ log.entityType }} #{{ log.entityId }}</td>
+                <td class="text-xs text-gray-500">
+                    {% for key, value in log.data %}
+                        <span class="font-bold">{{ key }}</span>: {{ value }}{% if not loop.last %}, {% endif %}
+                    {% endfor %}
+                </td>
+                <td class="text-xs text-gray-600">{{ log.performedBy ?? '—' }}</td>
+                <td class="text-xs text-gray-400 font-mono">{{ log.ipAddress ?? '—' }}</td>
+            </tr>
+            {% else %}
+            <tr>
+                <td colspan="6" class="!text-center !py-12 text-gray-400 font-bold text-sm">Aucun log.</td>
+            </tr>
+            {% endfor %}
+        </tbody>
+    </table>
+</div>
+
+{% if logs.getTotalItemCount > 30 %}
+<div class="flex justify-center gap-2 mt-6">
+    {% for page in 1..logs.getPageCount %}
+        {% if page == logs.getCurrentPageNumber %}
+            <span class="admin-page-active text-xs font-black">{{ page }}</span>
+        {% else %}
+            <a href="{{ path('app_admin_logs', {page: page}) }}" class="admin-page-link text-xs font-black hover:bg-gray-100 transition-all">{{ page }}</a>
+        {% endif %}
+    {% endfor %}
+</div>
+{% endif %}
+{% endblock %}
diff --git a/tests/Entity/AuditLogTest.php b/tests/Entity/AuditLogTest.php
new file mode 100644
index 0000000..b562bc4
--- /dev/null
+++ b/tests/Entity/AuditLogTest.php
@@ -0,0 +1,50 @@
+<?php
+
+namespace App\Tests\Entity;
+
+use App\Entity\AuditLog;
+use PHPUnit\Framework\TestCase;
+
+class AuditLogTest extends TestCase
+{
+    public function testConstructor(): void
+    {
+        $log = new AuditLog('order_created', 'BilletBuyer', 42);
+
+        self::assertNull($log->getId());
+        self::assertSame('order_created', $log->getAction());
+        self::assertSame('BilletBuyer', $log->getEntityType());
+        self::assertSame(42, $log->getEntityId());
+        self::assertSame([], $log->getData());
+        self::assertNull($log->getPerformedBy());
+        self::assertNull($log->getIpAddress());
+        self::assertInstanceOf(\DateTimeImmutable::class, $log->getCreatedAt());
+    }
+
+    public function testSetData(): void
+    {
+        $log = new AuditLog('test', 'Entity');
+        $result = $log->setData(['key' => 'value']);
+
+        self::assertSame(['key' => 'value'], $log->getData());
+        self::assertSame($log, $result);
+    }
+
+    public function testSetPerformedBy(): void
+    {
+        $log = new AuditLog('test', 'Entity');
+        $result = $log->setPerformedBy('admin@test.fr');
+
+        self::assertSame('admin@test.fr', $log->getPerformedBy());
+        self::assertSame($log, $result);
+    }
+
+    public function testSetIpAddress(): void
+    {
+        $log = new AuditLog('test', 'Entity');
+        $result = $log->setIpAddress('127.0.0.1');
+
+        self::assertSame('127.0.0.1', $log->getIpAddress());
+        self::assertSame($log, $result);
+    }
+}