diff --git a/tempest/api/network/admin/test_external_network_extension.py b/tempest/api/network/admin/test_external_network_extension.py
index 06cce48..3110aab 100644
--- a/tempest/api/network/admin/test_external_network_extension.py
+++ b/tempest/api/network/admin/test_external_network_extension.py
@@ -96,7 +96,8 @@
         self.addCleanup(self._try_delete_resource,
                         client.delete_network,
                         external_network['id'])
-        subnet = self.create_subnet(external_network, client=client)
+        subnet = self.create_subnet(external_network, client=client,
+                                    enable_dhcp=False)
         body = client.create_floatingip(
             floating_network_id=external_network['id'])
         created_floating_ip = body['floatingip']