diff --git a/nova/conf/base.py b/nova/conf/base.py
index 98dd21c8c2..d8ca1f56d6 100644
--- a/nova/conf/base.py
+++ b/nova/conf/base.py
@@ -63,6 +63,12 @@ entry.
     cfg.BoolOpt(
         'monkey_patch',
         default=False,
+        deprecated_for_removal=True,
+        deprecated_since='17.0.0',
+        deprecated_reason="""
+Monkey patching nova is not tested, not supported, and is a barrier
+for interoperability.
+""",
         help="""
 Determine if monkey patching should be applied.
 
@@ -74,6 +80,12 @@ Related options:
     cfg.ListOpt(
         'monkey_patch_modules',
         default=['nova.compute.api:nova.notifications.notify_decorator'],
+        deprecated_for_removal=True,
+        deprecated_since='17.0.0',
+        deprecated_reason="""
+Monkey patching nova is not tested, not supported, and is a barrier
+for interoperability.
+""",
         help="""
 List of modules/decorators to monkey patch.
 
@@ -83,7 +95,6 @@ modules.
 Possible values:
 
 * nova.compute.api:nova.notifications.notify_decorator
-* nova.api.ec2.cloud:nova.notifications.notify_decorator
 * [...]
 
 Related options:
diff --git a/nova/conf/notifications.py b/nova/conf/notifications.py
index 42fae1a85f..a1381c16fb 100644
--- a/nova/conf/notifications.py
+++ b/nova/conf/notifications.py
@@ -67,6 +67,14 @@ API service.
         'default_publisher_id',
         default='$my_ip',
         deprecated_group='DEFAULT',
+        deprecated_for_removal=True,
+        deprecated_since='17.0.0',
+        deprecated_reason="""
+This option is only used when ``monkey_patch=True`` and
+``monkey_patch_modules`` is configured to specify the legacy notify_decorator.
+Since the monkey_patch and monkey_patch_modules options are deprecated, this
+option is also deprecated.
+""",
         help="""
 Default publisher_id for outgoing notifications. If you consider routing
 notifications using different publisher, change this value accordingly.
diff --git a/nova/notifications/base.py b/nova/notifications/base.py
index 8396b63779..1421e74592 100644
--- a/nova/notifications/base.py
+++ b/nova/notifications/base.py
@@ -46,6 +46,8 @@ LOG = log.getLogger(__name__)
 CONF = nova.conf.CONF
 
 
+# TODO(mriedem): Remove this when CONF.monkey_patch, CONF.monkey_patch_modules
+# and CONF.default_publisher_id are removed in Rocky.
 def notify_decorator(name, fn):
     """Decorator for notify which is used from utils.monkey_patch().
 
diff --git a/nova/utils.py b/nova/utils.py
index c55cdabc94..6ee945b035 100644
--- a/nova/utils.py
+++ b/nova/utils.py
@@ -498,8 +498,9 @@ def format_remote_path(host, path):
     return "%s:%s" % (safe_ip_format(host), path)
 
 
+# TODO(mriedem): Remove this in Rocky.
 def monkey_patch():
-    """If the CONF.monkey_patch set as True,
+    """DEPRECATED: If the CONF.monkey_patch set as True,
     this function patches a decorator
     for all functions in specified modules.
     You can set decorators for each modules
@@ -517,6 +518,7 @@ def monkey_patch():
     # If CONF.monkey_patch is not True, this function do nothing.
     if not CONF.monkey_patch:
         return
+    LOG.warning('Monkey patching nova is deprecated for removal.')
     if six.PY2:
         is_method = inspect.ismethod
     else:
diff --git a/releasenotes/notes/deprecate-monkey-patch-5cd654924694b9ae.yaml b/releasenotes/notes/deprecate-monkey-patch-5cd654924694b9ae.yaml
new file mode 100644
index 0000000000..3b46a235e2
--- /dev/null
+++ b/releasenotes/notes/deprecate-monkey-patch-5cd654924694b9ae.yaml
@@ -0,0 +1,17 @@
+---
+deprecations:
+  - |
+    The following configuration options are deprecated for removal:
+
+    - ``[DEFAULT]/monkey_patch``
+    - ``[DEFAULT]/monkey_patch_modules``
+
+    Monkey patching nova is not tested, not supported, and is a barrier to
+    interoperability. If you have code which relies on monkey patching
+    decorators, for example, for notifications, please propose those changes
+    upstream.
+
+    As a result, the following option is also deprecated for removal since it
+    is only used when specified with ``[DEFAULT]/monkey_patch_modules``:
+
+    - ``[notifications]/default_publisher_id``