The Osiris blue (Cupido osiris) is a butterfly in the family Lycaenidae. It is found in South Europe, Asia Minor, southern Siberia, the Alay Mountains, Tian-Shan, Dzhungarsky Alatau, the Altai Region, the Sayan mountains, Lake Baikal and Mongolia. The larvae feed on Onobrychis and Leguminosae species.