diff --git a/neutron/agent/dhcp/agent.py b/neutron/agent/dhcp/agent.py
index 4602a3c4c53..c4b38885656 100644
--- a/neutron/agent/dhcp/agent.py
+++ b/neutron/agent/dhcp/agent.py
@@ -277,6 +277,10 @@ class DhcpAgent(manager.Manager):
                 if self.call_driver('enable', network):
                     dhcp_network_enabled = True
                     self.cache.put(network)
+                    # After enabling dhcp for network, mark all existing
+                    # ports as ready. So that the status of ports which are
+                    # created before enabling dhcp can be updated.
+                    self.dhcp_ready_ports |= {p.id for p in network.ports}
                 break
 
         if enable_metadata and dhcp_network_enabled:
diff --git a/neutron/tests/functional/agent/test_dhcp_agent.py b/neutron/tests/functional/agent/test_dhcp_agent.py
index 041367c6c5b..383102d2d6b 100644
--- a/neutron/tests/functional/agent/test_dhcp_agent.py
+++ b/neutron/tests/functional/agent/test_dhcp_agent.py
@@ -19,6 +19,7 @@ import eventlet
 import fixtures
 import mock
 import netaddr
+from neutron_lib import constants as lib_const
 from oslo_config import fixture as fixture_config
 from oslo_utils import uuidutils
 
@@ -313,3 +314,20 @@ class DHCPAgentOVSTestCase(DHCPAgentOVSTestFramework):
             timeout=5,
             sleep=0.1,
             exception=RuntimeError("Stale metadata proxy didn't get killed"))
+
+    def test_notify_port_ready_after_enable_dhcp(self):
+        network = self.network_dict_for_dhcp()
+        dhcp_port = self.create_port_dict(
+            network.id, network.subnets[0].id,
+            '24:77:03:7d:00:4d', ip_address='192.168.10.11')
+        dhcp_port.device_owner = lib_const.DEVICE_OWNER_DHCP
+        network.ports.append(dhcp_port)
+        self.agent.start_ready_ports_loop()
+        self.configure_dhcp_for_network(network)
+        ports_to_send = {p.id for p in network.ports}
+        utils.wait_until_true(
+            lambda: self.mock_plugin_api.dhcp_ready_on_ports.called,
+            timeout=1,
+            sleep=0.1,
+            exception=RuntimeError("'dhcp_ready_on_ports' not be called"))
+        self.mock_plugin_api.dhcp_ready_on_ports.assert_called_with(ports_to_send)
diff --git a/neutron/tests/unit/agent/dhcp/test_agent.py b/neutron/tests/unit/agent/dhcp/test_agent.py
index 0cd5bb84157..4911df332df 100644
--- a/neutron/tests/unit/agent/dhcp/test_agent.py
+++ b/neutron/tests/unit/agent/dhcp/test_agent.py
@@ -467,6 +467,12 @@ class TestDhcpAgent(base.BaseTestCase):
         # should have been called with all ports again after the failure
         ready.assert_has_calls([mock.call(set(range(4)))] * 2)
 
+    def test_dhcp_ready_ports_updates_after_enable_dhcp(self):
+        dhcp = dhcp_agent.DhcpAgent(HOSTNAME)
+        self.assertEqual(set(), dhcp.dhcp_ready_ports)
+        dhcp.configure_dhcp_for_network(fake_network)
+        self.assertEqual({fake_port1.id}, dhcp.dhcp_ready_ports)
+
     def test_report_state_revival_logic(self):
         dhcp = dhcp_agent.DhcpAgentWithStateReport(HOSTNAME)
         with mock.patch.object(dhcp.state_rpc,