diff --git a/etc/l3_agent.ini b/etc/l3_agent.ini
index be0ab852bb5..a8efb63d222 100644
--- a/etc/l3_agent.ini
+++ b/etc/l3_agent.ini
@@ -20,6 +20,7 @@
 
 # If non-empty, the l3 agent can only configure a router that has the matching
 # router ID.
+# This option is deprecated and will be removed in the N release.
 # router_id =
 
 # When external_network_bridge is set, each L3 agent can be associated
diff --git a/neutron/agent/l3/config.py b/neutron/agent/l3/config.py
index 856ddecc2fa..78cd6eb3b3c 100644
--- a/neutron/agent/l3/config.py
+++ b/neutron/agent/l3/config.py
@@ -49,6 +49,7 @@ OPTS = [
                help=_("Send this many gratuitous ARPs for HA setup, if "
                       "less than or equal to 0, the feature is disabled")),
     cfg.StrOpt('router_id', default='',
+               deprecated_for_removal=True,
                help=_("If non-empty, the l3 agent can only configure a router "
                       "that has the matching router ID.")),
     cfg.BoolOpt('handle_internal_only_routers',
diff --git a/releasenotes/notes/deprecate-router_id-34aca9ea5ee9e789.yaml b/releasenotes/notes/deprecate-router_id-34aca9ea5ee9e789.yaml
new file mode 100644
index 00000000000..389ef87d5cd
--- /dev/null
+++ b/releasenotes/notes/deprecate-router_id-34aca9ea5ee9e789.yaml
@@ -0,0 +1,5 @@
+---
+prelude: >
+    Deprecate router_id option in order to prepare its removal in N cycle.
+upgrade:
+  - router_id option deprecation