Oeneis tarpeja is a species of butterfly in the Nymphalidae family. It is found from the Caucasus and Volga region across Kazakhstan and southern Siberia to the Amur region and Mongolia. In Ukraine this species is extinct in the mid-twentieth century. The habitat consists of steppe-clad plains and foothills. The wingspan is 45–50 mm. Adults are on wing from June to July. The larvae feed on Poa avena and Festuca ovina.