diff --git a/doc/reference/orm.rst b/doc/reference/orm.rst
index 1ef0b5ca422..7d2b3bd1ac6 100644
--- a/doc/reference/orm.rst
+++ b/doc/reference/orm.rst
@@ -332,6 +332,28 @@ dependencies are modified.
 
 .. note:: The related fields are computed in sudo mode.
 
+.. warning::
+
+    You cannot chain :class:`~odoo.fields.Many2many` or :class:`~odoo.fields.One2many` fields in ``related`` fields dependencies.
+
+    ``related`` can be used to refer to a :class:`~odoo.fields.One2many` or
+    :class:`~odoo.fields.Many2many` field on another model on the
+    condition that it's done through a ``Many2one`` relation on the current model.
+    ``One2many`` and ``Many2many`` are not supported and the results will not be
+    aggregated correctly::
+
+      m2o_id = fields.Many2one()
+      m2m_ids = fields.Many2many()
+      o2m_ids = fields.One2many()
+
+      # Supported
+      d_ids = fields.Many2many(related="m2o_id.m2m_ids")
+      e_ids = fields.One2many(related="m2o_id.o2m_ids")
+
+      # Won't work: use a custom Many2many computed field instead
+      f_ids = fields.Many2many(related="m2m_ids.m2m_ids")
+      g_ids = fields.One2many(related="o2m_ids.o2m_ids")
+
 .. _reference/fields/automatic:
 
 Automatic fields