diff --git a/oslo_serialization/msgpackutils.py b/oslo_serialization/msgpackutils.py
index ff7b267..01003bf 100644
--- a/oslo_serialization/msgpackutils.py
+++ b/oslo_serialization/msgpackutils.py
@@ -33,10 +33,10 @@ import functools
 import itertools
 import uuid
 from xmlrpc import client as xmlrpclib
+import zoneinfo
 
 import msgpack
 from oslo_utils import importutils
-from pytz import timezone
 
 netaddr = importutils.try_import("netaddr")
 
@@ -236,7 +236,7 @@ class DateTimeHandler(object):
             'microsecond': dt.microsecond,
         }
         if dt.tzinfo:
-            tz = dt.tzinfo.tzname(None)
+            tz = str(dt.tzinfo)
             dct['tz'] = tz
         return dumps(dct, registry=self._registry)
 
@@ -263,9 +263,9 @@ class DateTimeHandler(object):
                                minute=dct['minute'],
                                second=dct['second'],
                                microsecond=dct['microsecond'])
-        if 'tz' in dct:
-            tzinfo = timezone(dct['tz'])
-            dt = tzinfo.localize(dt)
+        if 'tz' in dct and dct['tz']:
+            tzinfo = zoneinfo.ZoneInfo(dct['tz'])
+            dt = dt.replace(tzinfo=tzinfo)
         return dt
 
 
diff --git a/oslo_serialization/tests/test_msgpackutils.py b/oslo_serialization/tests/test_msgpackutils.py
index a8a91e9..3acc70d 100644
--- a/oslo_serialization/tests/test_msgpackutils.py
+++ b/oslo_serialization/tests/test_msgpackutils.py
@@ -15,10 +15,10 @@
 import datetime
 import itertools
 from xmlrpc import client as xmlrpclib
+import zoneinfo
 
 import netaddr
 from oslotest import base as test_base
-from pytz import timezone
 
 from oslo_serialization import msgpackutils
 from oslo_utils import uuidutils
@@ -145,20 +145,22 @@ class MsgPackUtilsTest(test_base.BaseTestCase):
         self.assertEqual(today, _dumps_loads(today))
 
     def test_datetime_tz_clone(self):
-        eastern = timezone('US/Eastern')
+        eastern = zoneinfo.ZoneInfo('US/Eastern')
         now = datetime.datetime.now()
-        e_dt = eastern.localize(now)
+        e_dt = now.replace(tzinfo=eastern)
         e_dt2 = _dumps_loads(e_dt)
         self.assertEqual(e_dt, e_dt2)
         self.assertEqual(e_dt.strftime(_TZ_FMT), e_dt2.strftime(_TZ_FMT))
 
     def test_datetime_tz_different(self):
-        eastern = timezone('US/Eastern')
-        pacific = timezone('US/Pacific')
+        eastern = zoneinfo.ZoneInfo('US/Eastern')
+        pacific = zoneinfo.ZoneInfo('US/Pacific')
         now = datetime.datetime.now()
 
-        e_dt = eastern.localize(now)
-        p_dt = pacific.localize(now)
+        now = now.replace(tzinfo=eastern)
+        e_dt = now
+        now = now.replace(tzinfo=pacific)
+        p_dt = now
 
         self.assertNotEqual(e_dt, p_dt)
         self.assertNotEqual(e_dt.strftime(_TZ_FMT), p_dt.strftime(_TZ_FMT))
diff --git a/releasenotes/notes/implement-zoneinfo-to-remove-pytz-c136b33bbfbfe59f.yaml b/releasenotes/notes/implement-zoneinfo-to-remove-pytz-c136b33bbfbfe59f.yaml
new file mode 100644
index 0000000..24c7d7f
--- /dev/null
+++ b/releasenotes/notes/implement-zoneinfo-to-remove-pytz-c136b33bbfbfe59f.yaml
@@ -0,0 +1,6 @@
+---
+other:
+  - |
+    Implement zoneinfo to allow us to remove pytz's dependency. zoneinfo
+    was introduced by python 3.9, and the series 2023.2 (bobcat) set py39
+    as the minimal supported runtime, so we are able to remove pytz.
diff --git a/requirements.txt b/requirements.txt
index d8c62c4..d31beef 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -10,4 +10,4 @@
 pbr!=2.1.0,>=2.0.0 # Apache-2.0
 msgpack>=0.5.2 # Apache-2.0
 oslo.utils>=3.33.0 # Apache-2.0
-pytz>=2013.6 # MIT
+tzdata>=2022.4 # MIT