diff --git a/neutron_lib/api/definitions/__init__.py b/neutron_lib/api/definitions/__init__.py
index ed1be97d5..83b172435 100644
--- a/neutron_lib/api/definitions/__init__.py
+++ b/neutron_lib/api/definitions/__init__.py
@@ -21,6 +21,7 @@ from neutron_lib.api.definitions import firewall
 from neutron_lib.api.definitions import firewall_v2
 from neutron_lib.api.definitions import firewallrouterinsertion
 from neutron_lib.api.definitions import l3
+from neutron_lib.api.definitions import logging
 from neutron_lib.api.definitions import logging_resource
 from neutron_lib.api.definitions import network
 from neutron_lib.api.definitions import port
@@ -46,6 +47,7 @@ _ALL_API_DEFINITIONS = {
     firewall_v2,
     firewallrouterinsertion,
     l3,
+    logging,
     logging_resource,
     network,
     port,
diff --git a/neutron_lib/api/definitions/base.py b/neutron_lib/api/definitions/base.py
index 330bf0f0e..ca86e5303 100644
--- a/neutron_lib/api/definitions/base.py
+++ b/neutron_lib/api/definitions/base.py
@@ -90,6 +90,7 @@ KNOWN_EXTENSIONS = (
     'flavors',
     'l3-ha',
     'l3_agent_scheduler',
+    'logging',
     'metering',
     'multi-provider',
     'net-mtu',
diff --git a/neutron_lib/api/definitions/logging.py b/neutron_lib/api/definitions/logging.py
new file mode 100644
index 000000000..0bcf8827c
--- /dev/null
+++ b/neutron_lib/api/definitions/logging.py
@@ -0,0 +1,109 @@
+# All rights reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+from neutron_lib.api import converters
+from neutron_lib.db import constants as db_const
+
+# The alias of the extension.
+ALIAS = 'logging'
+
+# Whether or not this extension is simply signaling behavior to the user
+# or it actively modifies the attribute map.
+IS_SHIM_EXTENSION = False
+
+# Whether the extension is marking the adoption of standardattr model for
+# legacy resources, or introducing new standardattr attributes. False or
+# None if the standardattr model is adopted since the introduction of
+# resource extension.
+# If this is True, the alias for the extension should be prefixed with
+# 'standard-attr-'.
+IS_STANDARD_ATTR_EXTENSION = False
+
+# The name of the extension.
+NAME = 'Logging API Extension'
+
+# A prefix for API resources. An empty prefix means that the API is going
+# to be exposed at the v2/ level as any other core resource.
+API_PREFIX = '/log'
+
+# The description of the extension.
+DESCRIPTION = ("Provides a logging API for resources such as "
+               "security group and firewall.")
+
+# A timestamp of when the extension was introduced.
+UPDATED_TIMESTAMP = "2017-01-01T10:00:00-00:00"
+
+LOGS = 'logs'
+LOG_TYPES = 'loggable_resources'
+
+ACCEPT_EVENT = 'ACCEPT'
+DROP_EVENT = 'DROP'
+ALL_EVENT = 'ALL'
+LOG_EVENTS = [ACCEPT_EVENT, DROP_EVENT, ALL_EVENT]
+
+# Attribute Map
+RESOURCE_ATTRIBUTE_MAP = {
+    LOGS: {
+        'id': {'allow_post': False, 'allow_put': False,
+               'validate': {'type:uuid': None},
+               'is_visible': True,
+               'primary_key': True},
+        'project_id': {'allow_post': True, 'allow_put': False,
+                       'required_by_policy': True,
+                       'validate': {
+                           'type:string':
+                               db_const.PROJECT_ID_FIELD_SIZE},
+                       'is_visible': True},
+        'name': {'allow_post': True, 'allow_put': True,
+                 'validate': {'type:string': db_const.NAME_FIELD_SIZE},
+                 'default': '', 'is_visible': True},
+        'resource_type': {'allow_post': True, 'allow_put': False,
+                          'required_by_policy': True,
+                          'validate': {
+                              'type:string':
+                                  db_const.RESOURCE_TYPE_FIELD_SIZE},
+                          'is_visible': True},
+        'resource_id': {'allow_post': True, 'allow_put': False,
+                        'validate': {'type:uuid_or_none': None},
+                        'default': None, 'is_visible': True},
+        'event': {'allow_post': True, 'allow_put': False,
+                  'validate': {'type:values': LOG_EVENTS},
+                  'default': ALL_EVENT, 'is_visible': True},
+        'target_id': {'allow_post': True, 'allow_put': False,
+                      'validate': {'type:uuid_or_none': None},
+                      'default': None, 'is_visible': True},
+        'enabled': {'allow_post': True, 'allow_put': True,
+                    'is_visible': True, 'default': True,
+                    'convert_to': converters.convert_to_boolean},
+    },
+    LOG_TYPES: {
+        'type': {'allow_post': False, 'allow_put': False,
+                 'is_visible': True}},
+}
+
+# The subresource attribute map for the extension.  This extension has only
+# top level resources, not child resources, so this is set to an empty dict.
+SUB_RESOURCE_ATTRIBUTE_MAP = {}
+
+# The action map.
+ACTION_MAP = {}
+
+# The list of required extensions.
+REQUIRED_EXTENSIONS = []
+
+# The action status.
+ACTION_STATUS = {}
+
+# The list of optional extensions.
+OPTIONAL_EXTENSIONS = ['security-group', 'fwaas_v2']
diff --git a/neutron_lib/tests/unit/api/definitions/test_logging.py b/neutron_lib/tests/unit/api/definitions/test_logging.py
new file mode 100644
index 000000000..7ae5f5141
--- /dev/null
+++ b/neutron_lib/tests/unit/api/definitions/test_logging.py
@@ -0,0 +1,30 @@
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+from neutron_lib.api.definitions import logging as log_api
+from neutron_lib.tests.unit.api.definitions import base
+
+EXTENSION_ATTRIBUTES = (
+    'event',
+    'target_id',
+    'resource_type',
+    'enabled',
+    'resource_id',
+    'type',
+)
+
+
+class LoggingApiTestCase(base.DefinitionBaseTestCase):
+    extension_module = log_api
+    extension_attributes = EXTENSION_ATTRIBUTES
+    extension_resources = (log_api.LOGS,
+                           log_api.LOG_TYPES,)
diff --git a/releasenotes/notes/introduce-logging-api-031d00eb84d5d061.yaml b/releasenotes/notes/introduce-logging-api-031d00eb84d5d061.yaml
new file mode 100644
index 000000000..943f39de9
--- /dev/null
+++ b/releasenotes/notes/introduce-logging-api-031d00eb84d5d061.yaml
@@ -0,0 +1,3 @@
+---
+features:
+  - API definition for the logging extension for ``security_group`` resource.