The Rayoso Formation is a geological formation in the Neuquén Province of Argentina whose strata date back to the Aptian-Albian stages of the Early Cretaceous.

Dinosaur remains are among the fossils that have been recovered from the formation.

[1] The formation has a maximum thickness of 604 metres (1,982 ft) and has one member, the Pichi Neuquén Member.

The unit comprises sandstones deposited in a lacustrine environment.

[2] Indeterminate ceratosaurian remains located in Neuquén Province, Argentina.