The Altafjord (Norwegian: Altafjorden; Northern Sami: Álttávuonna; Kven: Alattionvuono[1]) is a fjord in Alta Municipality in Finnmark county, Norway.

The 38-kilometre (24 mi) long fjord stretches from the town of Alta in the south to the islands of Stjernøya and Seiland.

At Stjernøya and Seiland islands, the fjord splits into two straits before emptying into the Norwegian Sea.

A large number of prehistoric rock carvings have been found along the fjord, particularly at the bay Jiepmaluokta.

[6] During World War II there was a German naval base along the Kåfjorden, which branches off the main Altafjord.