Chukchi Sea is a marginal sea of the Arctic Ocean. It is bounded on the west by the De Long Strait, off Wrangel Island, and in the east by Point Barrow, Alaska, beyond which lies the Beaufort Sea. The Bering Strait forms its southernmost limit and connects it to the Bering Sea and the Pacific Ocean. The principal port on the Chukchi Sea is Uelen in Russia. The International Date Line crosses the Chukchi Sea from northwest to southeast. It is displaced eastwards to avoid Wrangel Island as well as the Chukotka Autonomous Okrug on the Russian mainland.

Die Tschuktschensee (engl. Chukchi Sea, russ. Чуко́тское мо́ре/Tschukotskoje more) ist ein Randmeer des Nordpolarmeeres.