diff --git a/Lib/mimetypes.py b/Lib/mimetypes.py
index dad3813e39dbae..021ae985b40eb0 100644
--- a/Lib/mimetypes.py
+++ b/Lib/mimetypes.py
@@ -552,6 +552,8 @@ def _default_mime_types():
         '.csv'    : 'text/csv',
         '.html'   : 'text/html',
         '.htm'    : 'text/html',
+        '.md'     : 'text/markdown',
+        '.markdown': 'text/markdown',
         '.n3'     : 'text/n3',
         '.txt'    : 'text/plain',
         '.bat'    : 'text/plain',
diff --git a/Misc/NEWS.d/next/Library/2020-01-14-09-46-51.bpo-39324.qUcDrM.rst b/Misc/NEWS.d/next/Library/2020-01-14-09-46-51.bpo-39324.qUcDrM.rst
new file mode 100644
index 00000000000000..357d5a26fee743
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2020-01-14-09-46-51.bpo-39324.qUcDrM.rst
@@ -0,0 +1 @@
+Add mime type mapping for .md <-> text/markdown