diff --git a/aodh/notifier/heat.py b/aodh/notifier/heat.py
index 5cf53c79b..aa405b5a2 100644
--- a/aodh/notifier/heat.py
+++ b/aodh/notifier/heat.py
@@ -13,7 +13,6 @@
 #    limitations under the License.
 
 from oslo_log import log
-from oslo_utils import uuidutils
 import six
 
 from aodh import keystone_client as aodh_keystone
@@ -42,18 +41,6 @@ class TrustHeatAlarmNotifier(notifier.AlarmNotifier):
     - Heat top/root stack ID.
     - Heat autoscaling group ID.
     - The failed Octavia pool members.
-
-    In order to find which autoscaling group member that the failed pool member
-    belongs to, there are two ways supported(both ways require specific
-    definition in the Heat template):
-
-    1. The autoscaling group member resource ID is saved in the Octavia member
-       tag, the user should define that using 'tags' property of the
-       OS::Octavia::PoolMember resource. So, only Octavia stable/stein or later
-       versions are supported.
-    2. User customizes the autoscaling group member resource identifier
-       according to
-       https://docs.openstack.org/heat/latest/template_guide/composition.html#making-your-template-resource-more-transparent
     """
 
     def __init__(self, conf):
@@ -92,25 +79,20 @@ class TrustHeatAlarmNotifier(notifier.AlarmNotifier):
         )
 
         for member in unhealthy_members:
-            for tag in member.get("tags", []):
-                if uuidutils.is_uuid_like(tag):
-                    unhealthy_resources.append(tag)
+            target_resources = heat_client.resources.list(
+                stack_id, nested_depth=3,
+                filters={"physical_resource_id": member["id"]}
+            )
+            if len(target_resources) > 0:
+                # There should be only one item.
+                unhealthy_resources.append(
+                    target_resources[0].parent_resource
+                )
 
         if not unhealthy_resources:
-            # Fall back to search resource by the pool member ID.
-            for member in unhealthy_members:
-                target_resources = heat_client.resources.list(
-                    stack_id, nested_depth=3, filters={"id": member["id"]})
-                if len(target_resources) > 0:
-                    # There should be only one item.
-                    unhealthy_resources.append(
-                        target_resources[0].resource_name)
-
-            # If we still can't find expected resources, do nothing.
-            if not unhealthy_resources:
-                LOG.warning("No unhealthy resource found for the alarm %s",
-                            alarm_id)
-                return
+            LOG.warning("No unhealthy resource found for the alarm %s",
+                        alarm_id)
+            return
 
         try:
             for res in unhealthy_resources:
diff --git a/aodh/tests/unit/notifier/test_heat.py b/aodh/tests/unit/notifier/test_heat.py
index 459f3c5d0..7fbf83420 100644
--- a/aodh/tests/unit/notifier/test_heat.py
+++ b/aodh/tests/unit/notifier/test_heat.py
@@ -21,42 +21,7 @@ from aodh.tests.unit.notifier import base
 
 class TestTrustHeatAlarmNotifier(base.TestNotifierBase):
     @mock.patch("aodh.keystone_client.get_heat_client_from_trust")
-    def test_notify_with_tags(self, mock_heatclient):
-        action = netutils.urlsplit("trust+autohealer://fake_trust_id:delete@")
-        alarm_id = "fake_alarm_id"
-        alarm_name = "fake_alarm_name"
-        severity = "low"
-        previous = "ok"
-        current = "alarm"
-        reason = "no good reason"
-        reason_data = {
-            "stack_id": "fake_stack_id",
-            "asg_id": "fake_asg_id",
-            "unhealthy_members": [
-                {"tags": ["3bd8bc5a-7632-11e9-84cd-00224d6b7bc1"]}
-            ]
-        }
-
-        notifier = heat_notifier.TrustHeatAlarmNotifier(self.conf)
-        notifier.notify(action, alarm_id, alarm_name, severity, previous,
-                        current, reason, reason_data)
-
-        mock_heatclient.assert_called_once_with(self.conf, "fake_trust_id")
-
-        mock_client = mock_heatclient.return_value
-        mock_client.resources.mark_unhealthy.assert_called_once_with(
-            "fake_asg_id",
-            "3bd8bc5a-7632-11e9-84cd-00224d6b7bc1",
-            True,
-            "unhealthy load balancer member"
-        )
-
-        mock_client.stacks.update.assert_called_once_with(
-            "fake_stack_id", existing=True
-        )
-
-    @mock.patch("aodh.keystone_client.get_heat_client_from_trust")
-    def test_notify_without_tags(self, mock_heatclient):
+    def test_notify(self, mock_heatclient):
         action = netutils.urlsplit("trust+autohealer://fake_trust_id:delete@")
         alarm_id = "fake_alarm_id"
         alarm_name = "fake_alarm_name"
@@ -74,7 +39,7 @@ class TestTrustHeatAlarmNotifier(base.TestNotifierBase):
 
         class FakeResource(object):
             def __init__(self, resource_name):
-                self.resource_name = resource_name
+                self.parent_resource = resource_name
 
         mock_client = mock_heatclient.return_value
         mock_client.resources.list.return_value = [