diff --git a/doc/api/deprecations.md b/doc/api/deprecations.md
index 695f07fd42da75..1f2de2ed373d2f 100644
--- a/doc/api/deprecations.md
+++ b/doc/api/deprecations.md
@@ -1282,6 +1282,9 @@ The [`util.log()`][] API is deprecated.
 
 <!-- YAML
 changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/50488
+    description: Runtime deprecation.
   - version: v6.12.0
     pr-url: https://github.com/nodejs/node/pull/10116
     description: A deprecation code has been assigned.
@@ -1290,7 +1293,7 @@ changes:
     description: Documentation-only deprecation.
 -->
 
-Type: Documentation-only
+Type: Runtime
 
 The [`util._extend()`][] API is deprecated.
 
diff --git a/lib/util.js b/lib/util.js
index 9ddb332f866355..e1f005369d5873 100644
--- a/lib/util.js
+++ b/lib/util.js
@@ -375,7 +375,9 @@ function _exceptionWithHostPort(...args) {
 module.exports = {
   _errnoException,
   _exceptionWithHostPort,
-  _extend,
+  _extend: deprecate(_extend,
+                     'The `util._extend` API is deprecated. Please use Object.assign() instead.',
+                     'DEP0060'),
   callbackify,
   debug: debuglog,
   debuglog,