Bagasis was a Parthian prince, who played an important role in Parthian politics from 148/7 BC, where he was appointed the governor of the newly conquered region of Media by his brother and king Mithridates I. Bagasis was initially suggested by the modern historian Gholamreza F. Assar (2005) to have ruled as king briefly in 126 BC, but he later retracted this suggestion (2009). Bagasis was survived by an unnamed son, who occupied high offices under Mithridates II.