Kolyuchinskaya Bay is a large bay in the Chukchi Sea on the northern shore of the Chukotka Peninsula, Russia. To the west is Cape Vankarem and to the east Neskynpil'gyn Lagoon and Cape Serdtse-Kamen. The length of the bay is 100 km. Its mouth is only 2.8 km because of the Serykh Gusey Islands and Belyaka Spit (Kosa Belyaka), separate it from the Arctic Ocean. The width increases to 37 km as it goes southwards and inland.