diff --git a/modoboa/admin/management/commands/subcommands/_repair.py b/modoboa/admin/management/commands/subcommands/_repair.py
index 213f40313..029e72ae1 100644
--- a/modoboa/admin/management/commands/subcommands/_repair.py
+++ b/modoboa/admin/management/commands/subcommands/_repair.py
@@ -62,7 +62,12 @@ class Repair(BaseCommand):
                     elif isinstance(obj, models.DomainAlias):
                         admin = obj.target.admins.first()
                     else:
-                        admin = obj.domain.admins.first()
+                        if obj.domain:
+                            admin = obj.domain.admins.first()
+                        else:
+                            # Alias is an internal alias for domain alias
+                            # we don't care if it's not owned
+                            continue
                     if not admin:
                         # domain has no admin. use the first superuser found
                         admin = User.objects.filter(is_superuser=True,
diff --git a/modoboa/admin/tests/test_repair.py b/modoboa/admin/tests/test_repair.py
index 1ea383015..e93efa932 100644
--- a/modoboa/admin/tests/test_repair.py
+++ b/modoboa/admin/tests/test_repair.py
@@ -39,3 +39,8 @@ class RepairTestCase(ModoTestCase):
         management.call_command("modo", "repair", "--quiet", "--dry-run")
         # assert its not fixed
         self.assertIs(get_object_owner(mbox), None)
+
+    def test_management_command_with_nul_domain(self):
+        """ Just assume nothing raise when an alias has no domain"""
+        models.Alias.objects.create(address='@modoboa.xxx')
+        management.call_command("modo", "repair", "--quiet")