diff --git a/ceilometer/publisher/gnocchi.py b/ceilometer/publisher/gnocchi.py
index 38bb088dde..ae19309901 100644
--- a/ceilometer/publisher/gnocchi.py
+++ b/ceilometer/publisher/gnocchi.py
@@ -15,6 +15,7 @@
 from collections import defaultdict
 import hashlib
 import itertools
+import json
 import operator
 import pkg_resources
 import threading
@@ -28,7 +29,6 @@ from oslo_utils import timeutils
 import six
 import six.moves.urllib.parse as urlparse
 from stevedore import extension
-import ujson
 
 from ceilometer import declarative
 from ceilometer import gnocchi_client
@@ -502,7 +502,7 @@ class GnocchiPublisher(publisher.ConfigPublisherBase):
     def _search_resource(self, resource_type, query):
         try:
             return self._gnocchi.resource.search(
-                resource_type, ujson.loads(query))
+                resource_type, json.loads(query))
         except Exception:
             LOG.error("Fail to search resource type %{resource_type}s "
                       "with '%{query}s'",
diff --git a/ceilometer/publisher/http.py b/ceilometer/publisher/http.py
index 3ae93fa52a..e57370e319 100644
--- a/ceilometer/publisher/http.py
+++ b/ceilometer/publisher/http.py
@@ -13,12 +13,13 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
+import json
+
 from oslo_log import log
 from oslo_utils import strutils
 import requests
 from requests import adapters
 from six.moves.urllib import parse as urlparse
-import ujson
 
 from ceilometer import publisher
 
@@ -154,7 +155,7 @@ class HttpPublisher(publisher.ConfigPublisherBase):
         if not data:
             LOG.debug('Data set is empty!')
             return
-        data = ujson.dumps(data)
+        data = json.dumps(data)
         LOG.trace('Message: %s', data)
         try:
             res = self.session.post(self.target, data=data,
diff --git a/ceilometer/tests/tempest/aodh/service/client.py b/ceilometer/tests/tempest/aodh/service/client.py
index 39d2cf8914..1043a05b1d 100644
--- a/ceilometer/tests/tempest/aodh/service/client.py
+++ b/ceilometer/tests/tempest/aodh/service/client.py
@@ -13,11 +13,12 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+import json
+
 from six.moves.urllib import parse as urllib
 from tempest import config
 from tempest.lib.common import rest_client
 from tempest import manager
-import ujson
 
 CONF = config.CONF
 
@@ -28,10 +29,10 @@ class AlarmingClient(rest_client.RestClient):
     uri_prefix = "v2"
 
     def deserialize(self, body):
-        return ujson.loads(body.replace("\n", ""))
+        return json.loads(body.replace("\n", ""))
 
     def serialize(self, body):
-        return ujson.dumps(body)
+        return json.dumps(body)
 
     def list_alarms(self, query=None):
         uri = '%s/alarms' % self.uri_prefix
diff --git a/ceilometer/tests/unit/publisher/test_http.py b/ceilometer/tests/unit/publisher/test_http.py
index 9226644cfb..a5a53067d3 100644
--- a/ceilometer/tests/unit/publisher/test_http.py
+++ b/ceilometer/tests/unit/publisher/test_http.py
@@ -260,5 +260,5 @@ class TestHttpPublisher(base.BaseTestCase):
         with mock.patch.object(requests.Session, 'post') as post:
             publisher.publish_events(self.event_data)
             self.assertEqual(
-                '[{"some":"aa"},{"some":"aa"},{"some":"aa"}]',
+                '[{"some": "aa"}, {"some": "aa"}, {"some": "aa"}]',
                 post.call_args[1]['data'])
diff --git a/ceilometer/tests/unit/publisher/test_utils.py b/ceilometer/tests/unit/publisher/test_utils.py
index ca9ee8ab2a..a882b964b8 100644
--- a/ceilometer/tests/unit/publisher/test_utils.py
+++ b/ceilometer/tests/unit/publisher/test_utils.py
@@ -14,8 +14,9 @@
 # under the License.
 """Tests for ceilometer/publisher/utils.py
 """
+import json
+
 from oslotest import base
-import ujson
 
 from ceilometer.publisher import utils
 
@@ -104,7 +105,7 @@ class TestSignature(base.BaseTestCase):
         data['message_signature'] = utils.compute_signature(
             data,
             'not-so-secret')
-        jsondata = ujson.loads(ujson.dumps(data))
+        jsondata = json.loads(json.dumps(data))
         self.assertTrue(utils.verify_signature(jsondata, 'not-so-secret'))
 
     def test_verify_unicode_symbols(self):
@@ -114,7 +115,7 @@ class TestSignature(base.BaseTestCase):
         data['message_signature'] = utils.compute_signature(
             data,
             'not-so-secret')
-        jsondata = ujson.loads(ujson.dumps(data))
+        jsondata = json.loads(json.dumps(data))
         self.assertTrue(utils.verify_signature(jsondata, 'not-so-secret'))
 
     def test_verify_no_secret(self):
diff --git a/requirements.txt b/requirements.txt
index b978ac8a37..9282f42459 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -19,7 +19,6 @@ oslo.reports>=0.6.0 # Apache-2.0
 oslo.rootwrap>=2.0.0 # Apache-2.0
 pbr>=1.6 # Apache-2.0
 oslo.messaging>=5.12.0 # Apache-2.0
-ujson
 oslo.utils>=3.5.0 # Apache-2.0
 pysnmp<5.0.0,>=4.2.3 # BSD
 python-glanceclient>=2.0.0 # Apache-2.0