diff --git a/changelog.d/18064.doc b/changelog.d/18064.doc
new file mode 100644
index 00000000000..09f73c9b9b2
--- /dev/null
+++ b/changelog.d/18064.doc
@@ -0,0 +1 @@
+Document `tls` option for a worker instance in `instance_map`.
diff --git a/docs/usage/configuration/config_documentation.md b/docs/usage/configuration/config_documentation.md
index 74522a1e4e5..64392366cac 100644
--- a/docs/usage/configuration/config_documentation.md
+++ b/docs/usage/configuration/config_documentation.md
@@ -4465,6 +4465,10 @@ instance_map:
   worker1:
     host: localhost
     port: 8034
+  other:
+    host: localhost
+    port: 8035
+    tls: true
 ```
 Example configuration(#2, for UNIX sockets):
 ```yaml