Kosa River (Russian: Коса, Komi: Кöсва) is a river in Perm Krai, Russia, a right tributary of the Kama River. The river is 267 kilometres (166 mi) long and has a basin of 10,300 square kilometres (4,000 sq mi). The Kosa River freezes up in late October or November and stays icebound until April or early May. It starts in the extreme south of Kosinsky District and flows north. The mouth of the river is near the village of Ust-Kosa. Banks are lowland.