Atlasov Island (sometimes rendered as Atlasova Island, from ), also known as , is the northernmost island of the Kuril Islands, part of the Sakhalin Oblast in Russia. Located on the island is Alaid volcano, the highest volcano of the Kurils and one of the most active.
The island is named after Vladimir Atlasov, a 17th-century Russian explorer who incorporated the nearby Kamchatka Peninsula into Russia. It is essentially the cone of the submarine volcano Vulkan Alaid protruding above the Sea of Okhotsk to a height of . The island has an area of , and is currently uninhabited. Numerous pyroclastic cones dot the lower flanks of basaltic to basaltic andesite volcano, particularly on the NW and SE sides, including an offshore cone formed during the 1933–34 eruption.