The Ubaye is a river of southeastern France. It is long and flows through the Alpes-de-Haute-Provence department.
Its rises at the Col de Longet, in the Cottian Alps on the border with Italy. It flows generally southwest, through Saint-Paul-sur-Ubaye, Jausiers and Barcelonnette. It flows into the Lac de Serre-Ponçon (which is fed and drained by the Durance) near La Bréole.