diff --git a/docs/ref/settings.txt b/docs/ref/settings.txt
index 10f60b3b2e..e9c333081a 100644
--- a/docs/ref/settings.txt
+++ b/docs/ref/settings.txt
@@ -2048,6 +2048,10 @@ unpredictable value.
 :djadmin:`django-admin startproject <startproject>` automatically adds a
 randomly-generated ``SECRET_KEY`` to each new project.
 
+Uses of the key shouldn't assume that it's text or bytes. Every use should go
+through :func:`~django.utils.encoding.force_text` or
+:func:`~django.utils.encoding.force_bytes` to convert it to the desired type.
+
 Django will refuse to start if :setting:`SECRET_KEY` is not set.
 
 .. warning::