diff --git a/docs/topics/settings.rst b/docs/topics/settings.rst
index 6722ce9ed..90f13f3ef 100644
--- a/docs/topics/settings.rst
+++ b/docs/topics/settings.rst
@@ -98,6 +98,10 @@ class.
 The global defaults are located in the ``scrapy.settings.default_settings``
 module and documented in the :ref:`topics-settings-ref` section.
 
+Compatibility with pickle
+=========================
+
+Setting values must be :ref:`picklable <pickle-picklable>`.
 
 Import paths and classes
 ========================