diff --git a/Doc/whatsnew/3.15.rst b/Doc/whatsnew/3.15.rst
index 5379ac3abba227..7a8e747cb4e563 100644
--- a/Doc/whatsnew/3.15.rst
+++ b/Doc/whatsnew/3.15.rst
@@ -443,6 +443,7 @@ math
 mimetypes
 ---------
 
+* Add ``application/node`` MIME type for ``.cjs`` extension. (Contributed by John Franey in :gh:`140937`.)
 * Add ``application/toml``. (Contributed by Gil Forcada in :gh:`139959`.)
 * Rename ``application/x-texinfo`` to ``application/texinfo``.
   (Contributed by Charlie Lin in :gh:`140165`)
diff --git a/Lib/mimetypes.py b/Lib/mimetypes.py
index 48a9f430d45262..d6896fc4042cb4 100644
--- a/Lib/mimetypes.py
+++ b/Lib/mimetypes.py
@@ -486,6 +486,7 @@ def _default_mime_types():
         '.wiz'    : 'application/msword',
         '.nq'     : 'application/n-quads',
         '.nt'     : 'application/n-triples',
+        '.cjs'    : 'application/node',
         '.bin'    : 'application/octet-stream',
         '.a'      : 'application/octet-stream',
         '.dll'    : 'application/octet-stream',
diff --git a/Misc/NEWS.d/next/Core_and_Builtins/2025-11-04-12-18-06.gh-issue-140942.GYns6n.rst b/Misc/NEWS.d/next/Core_and_Builtins/2025-11-04-12-18-06.gh-issue-140942.GYns6n.rst
new file mode 100644
index 00000000000000..20cfeca1e71dca
--- /dev/null
+++ b/Misc/NEWS.d/next/Core_and_Builtins/2025-11-04-12-18-06.gh-issue-140942.GYns6n.rst
@@ -0,0 +1,2 @@
+Add ``.cjs`` to :mod:`mimetypes` to give CommonJS modules a MIME type of
+``application/node``.