Leontyeva Island – an island within the Bear Islands, the East Siberian Sea, the Republic of Sakha (Yakutia), Russia, located in the central part of the Medvezhii Islands, 7 km south of Pushkarev Island. It is the second largest after Krestovskiy Island. It has an elongated shape expanding to the north with a length of 13 km and a width of 1 km in the south up to 7 km in the northern part. It consists of two parallel mountain ranges up to 80 m high. Small, sometimes swampy, streams flow from the central highland to the northwest and east coasts. The shores are mostly steep and inaccessible, up to 22 m high. There are a lot of driftwoods on the island; mammoth bones were also frequently found. Flora and fauna include a rare short grass, moss, and lichen, and deers, bears, wolves, foxes, and small rodents coming from the mainland.
The island together with the other islands of the group was discovered in 1710 by Cossack Yakov Permiakov; however, it was mapped only in 1769 by geodesist-ensigns Ivan Leontyev, Ivan Lisov, and Aleksey Pushkarev. In honor of ensign I. Leontyev, the island was named in 1912 by members of the Hydrographic Expedition of the Arctic Ocean on the icebreakers “Taymyr” and “Vaygach.”