diff --git a/Doc/library/array.rst b/Doc/library/array.rst
--- a/Doc/library/array.rst
+++ b/Doc/library/array.rst
@@ -51,6 +51,11 @@
    (:c:type:`Py_UNICODE` which is :c:type:`wchar_t`). Depending on the
    platform, it can be 16 bits or 32 bits.
 
+   ``'u'`` will be removed together with the rest of the :c:type:`Py_UNICODE`
+   API.
+
+   .. deprecated-removed:: 3.3 4.0
+
 (2)
    The ``'q'`` and ``'Q'`` type codes are available only if
    the platform C compiler used to build Python supports C :c:type:`long long`,