diff --git a/NEWS b/NEWS
index 3c52e5ec1..7076939c5 100644
--- a/NEWS
+++ b/NEWS
@@ -3,6 +3,9 @@ Post-v3.3.0
    - ovs-appctl:
      * Added new option [-f|--format] to choose the output format, e.g. 'json'
        or 'text' (by default).
+   - Python:
+     * Added support for different output formats like 'json' to appctl.py and
+       Python's unixctl classes.
    - Userspace datapath:
      * Conntrack now supports 'random' flag for selecting ports in a range
        while natting and 'persistent' flag for selection of the IP address
diff --git a/python/ovs/unixctl/client.py b/python/ovs/unixctl/client.py
index 8283f99bb..8a6fcb1b9 100644
--- a/python/ovs/unixctl/client.py
+++ b/python/ovs/unixctl/client.py
@@ -14,6 +14,7 @@
 
 import os
 
+import ovs.json
 import ovs.jsonrpc
 import ovs.stream
 import ovs.util
@@ -41,10 +42,10 @@ class UnixctlClient(object):
             return error, None, None
 
         if reply.error is not None:
-            return 0, str(reply.error), None
+            return 0, reply.error, None
         else:
             assert reply.result is not None
-            return 0, None, str(reply.result)
+            return 0, None, reply.result
 
     def close(self):
         self._conn.close()
diff --git a/python/ovs/unixctl/server.py b/python/ovs/unixctl/server.py
index d24a7092c..0665eb837 100644
--- a/python/ovs/unixctl/server.py
+++ b/python/ovs/unixctl/server.py
@@ -12,6 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import argparse
 import copy
 import errno
 import os
@@ -35,6 +36,7 @@ class UnixctlConnection(object):
         assert isinstance(rpc, ovs.jsonrpc.Connection)
         self._rpc = rpc
         self._request_id = None
+        self._fmt = ovs.util.OutputFormat.TEXT
 
     def run(self):
         self._rpc.run()
@@ -63,10 +65,29 @@ class UnixctlConnection(object):
         return error
 
     def reply(self, body):
-        self._reply_impl(True, body)
+        assert body is None or isinstance(body, str)
+
+        if body is None:
+            body = ""
+
+        if self._fmt == ovs.util.OutputFormat.JSON:
+            body = {
+                "reply-format": "plain",
+                "reply": body
+            }
+
+        return self._reply_impl_json(True, body)
+
+    def reply_json(self, body):
+        self._reply_impl_json(True, body)
 
     def reply_error(self, body):
-        self._reply_impl(False, body)
+        assert body is None or isinstance(body, str)
+
+        if body is None:
+            body = ""
+
+        return self._reply_impl_json(False, body)
 
     # Called only by unixctl classes.
     def _close(self):
@@ -78,15 +99,11 @@ class UnixctlConnection(object):
         if not self._rpc.get_backlog():
             self._rpc.recv_wait(poller)
 
-    def _reply_impl(self, success, body):
+    def _reply_impl_json(self, success, body):
         assert isinstance(success, bool)
-        assert body is None or isinstance(body, str)
 
         assert self._request_id is not None
 
-        if body is None:
-            body = ""
-
         if success:
             reply = Message.create_reply(body, self._request_id)
         else:
@@ -133,6 +150,24 @@ def _unixctl_version(conn, unused_argv, version):
     conn.reply(version)
 
 
+def _unixctl_set_options(conn, argv, unused_aux):
+    assert isinstance(conn, UnixctlConnection)
+
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--format", default="text",
+                        choices=[fmt.name.lower()
+                                 for fmt in ovs.util.OutputFormat])
+
+    try:
+        args = parser.parse_args(args=argv)
+    except argparse.ArgumentError as e:
+        conn.reply_error(str(e))
+        return
+
+    conn._fmt = ovs.util.OutputFormat[args.format.upper()]
+    conn.reply(None)
+
+
 class UnixctlServer(object):
     def __init__(self, listener):
         assert isinstance(listener, ovs.stream.PassiveStream)
@@ -207,4 +242,7 @@ class UnixctlServer(object):
         ovs.unixctl.command_register("version", "", 0, 0, _unixctl_version,
                                      version)
 
+        ovs.unixctl.command_register("set-options", "[--format text|json]", 0,
+                                     2, _unixctl_set_options, None)
+
         return 0, UnixctlServer(listener)
diff --git a/python/ovs/util.py b/python/ovs/util.py
index 3dba022f8..272ca683d 100644
--- a/python/ovs/util.py
+++ b/python/ovs/util.py
@@ -15,11 +15,19 @@
 import os
 import os.path
 import sys
+import enum
 
 PROGRAM_NAME = os.path.basename(sys.argv[0])
 EOF = -1
 
 
+@enum.unique
+# FIXME: Use @enum.verify(enum.NAMED_FLAGS) from Python 3.11 when available.
+class OutputFormat(enum.IntFlag):
+    TEXT = 1 << 0
+    JSON = 1 << 1
+
+
 def abs_file_name(dir_, file_name):
     """If 'file_name' starts with '/', returns a copy of 'file_name'.
     Otherwise, returns an absolute path to 'file_name' considering it relative
diff --git a/tests/appctl.py b/tests/appctl.py
index e5cc28138..cf3ea3642 100644
--- a/tests/appctl.py
+++ b/tests/appctl.py
@@ -37,6 +37,18 @@ def connect_to_target(target):
     return client
 
 
+def reply_to_string(reply, fmt=ovs.util.OutputFormat.TEXT):
+    if fmt == ovs.util.OutputFormat.TEXT:
+        body = str(reply)
+
+        if body and not body.endswith("\n"):
+            body += "\n"
+
+        return body
+    else:
+        return ovs.json.to_string(reply)
+
+
 def main():
     parser = argparse.ArgumentParser(description="Python Implementation of"
                                      " ovs-appctl.")
@@ -49,30 +61,42 @@ def main():
                         help="Arguments to the command.")
     parser.add_argument("-T", "--timeout", metavar="SECS",
                         help="wait at most SECS seconds for a response")
+    parser.add_argument("-f", "--format", metavar="FMT",
+                        help="Output format.", default="text",
+                        choices=[fmt.name.lower()
+                                 for fmt in ovs.util.OutputFormat])
     args = parser.parse_args()
 
     signal_alarm(int(args.timeout) if args.timeout else None)
 
     ovs.vlog.Vlog.init()
     target = args.target
+    format = ovs.util.OutputFormat[args.format.upper()]
     client = connect_to_target(target)
+
+    if format != ovs.util.OutputFormat.TEXT:
+        err_no, error, _ = client.transact(
+            "set-options", ["--format", args.format])
+
+        if err_no:
+            ovs.util.ovs_fatal(err_no, "%s: transaction error" % target)
+        elif error is not None:
+            sys.stderr.write(reply_to_string(error))
+            ovs.util.ovs_error(0, "%s: server returned an error" % target)
+            sys.exit(2)
+
     err_no, error, result = client.transact(args.command, args.argv)
     client.close()
 
     if err_no:
         ovs.util.ovs_fatal(err_no, "%s: transaction error" % target)
     elif error is not None:
-        sys.stderr.write(error)
-        if error and not error.endswith("\n"):
-            sys.stderr.write("\n")
-
+        sys.stderr.write(reply_to_string(error))
         ovs.util.ovs_error(0, "%s: server returned an error" % target)
         sys.exit(2)
     else:
         assert result is not None
-        sys.stdout.write(result)
-        if result and not result.endswith("\n"):
-            sys.stdout.write("\n")
+        sys.stdout.write(reply_to_string(result, format))
 
 
 if __name__ == '__main__':
diff --git a/tests/unixctl-py.at b/tests/unixctl-py.at
index 724006118..92f557b67 100644
--- a/tests/unixctl-py.at
+++ b/tests/unixctl-py.at
@@ -100,6 +100,7 @@ The available commands are:
   exit
   help
   log                     [[arg ...]]
+  set-options             [[--format text|json]]
   version
   vlog/close
   vlog/list
@@ -112,6 +113,8 @@ AT_CHECK([PYAPPCTL_PY -t test-unixctl.py help], [0], [expout])
 AT_CHECK([ovs-vsctl --version | sed 's/ovs-vsctl/test-unixctl.py/' | head -1 > expout])
 AT_CHECK([APPCTL -t test-unixctl.py version], [0], [expout])
 AT_CHECK([PYAPPCTL_PY -t test-unixctl.py version], [0], [expout])
+AT_CHECK_UNQUOTED([PYAPPCTL_PY -t test-unixctl.py --format json version], [0], [dnl
+{"reply":"$(cat expout)","reply-format":"plain"}])
 
 AT_CHECK([APPCTL -t test-unixctl.py echo robot ninja], [0], [stdout])
 AT_CHECK([cat stdout | sed -e "s/u'/'/g"], [0], [dnl
