The Oenus (Ancient Greek: Οἰνοῦς, Greek: Οινούντας - Oinountas, also called Kelefina) is a river in the Peloponnese peninsula, southern Greece.

Parnon, and, after flowing in a general southwesterly direction, falls into the Eurotas, at the distance of little more than a mile from Sparta.

The principal tributary of the Oenus was the Gorgylus (Greek: Γόργυλος, Polyb.

The municipal unit Oinountas, part of the municipality Sparta, was named after the river Oenus.

This article related to a river in Greece is a stub.