Alexey Ivanovich Nagayev (Russian: Алексей Иванович Нагаев, March 17, 1704, Sertyakino-January 8, 1781, Saint Petersburg) was a Russian hydrographer, cartographer and an admiral (since 1769). Coming from scanty noble family, he graduated from Petersburg Naval Academy and worked ibidem. During the Seven Years' War Nagayev headed the hydrographic expedition to the Prussian shores. He also compiled the first atlases of the Bering Sea and Baltic Sea (1752). Despite the absence of meridional grid, Nagayev's maps have been used for over fifty years. In 1764-65 Nagayev has been the supreme commander of the Kronstadt port. A bay in the Okhotsk Sea is named after him.