diff --git a/Doc/library/socket.rst b/Doc/library/socket.rst
--- a/Doc/library/socket.rst
+++ b/Doc/library/socket.rst
@@ -293,6 +293,11 @@
    TIPC related constants, matching the ones exported by the C socket API. See
    the TIPC documentation for more information.

+.. data:: AF_LINK
+
+  Availability: BSD, OSX.
+
+  .. versionadded:: 3.4

 .. data:: has_ipv6

diff --git a/Modules/socketmodule.c b/Modules/socketmodule.c
--- a/Modules/socketmodule.c
+++ b/Modules/socketmodule.c
@@ -5658,6 +5658,9 @@
     /* Alias to emulate 4.4BSD */
     PyModule_AddIntMacro(m, AF_ROUTE);
 #endif
+#ifdef AF_LINK
+    PyModule_AddIntMacro(m, AF_LINK);
+#endif
 #ifdef AF_ASH
     /* Ash */
     PyModule_AddIntMacro(m, AF_ASH);