In Greek sources, Ostanes is given as the name of one of the sons of the Achaemenid Persian emperor Darius (II) Nothos, and the grandfather of Darius (III) Codomannos. Aside from the name and relationship to the rulers, the sources do not have any information about the person.

The sources are Diodorus 17.5.5 and Plutarch Artax. 1.1.5. The latter