diff --git a/releasenotes/notes/deprecate-ceilometer-datasource-446b0be70fbce28b.yaml b/releasenotes/notes/deprecate-ceilometer-datasource-446b0be70fbce28b.yaml
new file mode 100644
index 000000000..430b97a91
--- /dev/null
+++ b/releasenotes/notes/deprecate-ceilometer-datasource-446b0be70fbce28b.yaml
@@ -0,0 +1,7 @@
+---
+deprecations:
+  - |
+    Ceilometer Datasource has been deprecated since its API has been
+    deprecated in Ocata cycle. Watcher has supported Ceilometer for some
+    releases after Ocata to let users migrate to Gnocchi/Monasca datasources.
+    Since Train release, Ceilometer support will be removed.
diff --git a/watcher/conf/ceilometer_client.py b/watcher/conf/ceilometer_client.py
index 2ffbb9181..6d78a2662 100644
--- a/watcher/conf/ceilometer_client.py
+++ b/watcher/conf/ceilometer_client.py
@@ -24,14 +24,32 @@ ceilometer_client = cfg.OptGroup(name='ceilometer_client',
 CEILOMETER_CLIENT_OPTS = [
     cfg.StrOpt('api_version',
                default='2',
+               deprecated_for_removal=True,
+               deprecated_since="1.13.0",
+               deprecated_reason="""
+               Ceilometer API is deprecated since Ocata release.
+               Any related configuration options are deprecated too.
+               """,
                help='Version of Ceilometer API to use in '
                     'ceilometerclient.'),
     cfg.StrOpt('endpoint_type',
                default='internalURL',
+               deprecated_for_removal=True,
+               deprecated_since="1.13.0",
+               deprecated_reason="""
+               Ceilometer API is deprecated since Ocata release.
+               Any related configuration options are deprecated too.
+               """,
                help='Type of endpoint to use in ceilometerclient. '
                     'Supported values: internalURL, publicURL, adminURL. '
                     'The default is internalURL.'),
     cfg.StrOpt('region_name',
+               deprecated_for_removal=True,
+               deprecated_since="1.13.0",
+               deprecated_reason="""
+               Ceilometer API is deprecated since Ocata release.
+               Any related configuration options are deprecated too.
+               """,
                help='Region in Identity service catalog to use for '
                     'communication with the OpenStack service.')]
 
diff --git a/watcher/datasource/ceilometer.py b/watcher/datasource/ceilometer.py
index 424011bd5..3965e3b41 100644
--- a/watcher/datasource/ceilometer.py
+++ b/watcher/datasource/ceilometer.py
@@ -19,6 +19,7 @@
 import datetime
 
 from ceilometerclient import exc
+from oslo_log import log
 from oslo_utils import timeutils
 
 from watcher._i18n import _
@@ -27,6 +28,9 @@ from watcher.common import exception
 from watcher.datasource import base
 
 
+LOG = log.getLogger(__name__)
+
+
 class CeilometerHelper(base.DataSourceBase):
 
     NAME = 'ceilometer'
@@ -36,6 +40,9 @@ class CeilometerHelper(base.DataSourceBase):
         """:param osc: an OpenStackClients instance"""
         self.osc = osc if osc else clients.OpenStackClients()
         self.ceilometer = self.osc.ceilometer()
+        LOG.warning("Ceilometer API is deprecated and Ceilometer Datasource "
+                    "module is no longer maintained. We recommend to use "
+                    "Gnocchi instead.")
 
     @staticmethod
     def format_query(user_id, tenant_id, resource_id,