Leontyev, Leontief, Leontiev, Leontjew, Leontjev, or Leont'ev () and Leontyeva (Леонтьева; feminine) is a Russian surname. Notable people with the surname include: Alexei Leontyev (1917–?), Soviet mathematician Alexei Leontyev (1716–1786), one of the first Russian sinologists Aleksei N. Leontiev (1903–1979), Soviet psychologist, the founder of activity theory Aleksei A. Leontiev (1936–2004), Soviet psychologist and linguist, one of the founders of the Soviet psycholinguistics, the son of Aleksei N. Leontiev Konstantin Leontiev (1831–1891), Russian philosopher Lev Leontiev (1901–?), Soviet economist Mikhail Leontiev (born 1958), Russian reporter working for Channel One Oleg Leontyev (1920–?), Soviet geomorphologist Sergei Leontiev (1879 or 1880 – after 1932), Russian politician Valentina Leontieva (1923–2007), Soviet TV anchor Valery Leontiev (born 1949), Russian pop singer Viktor Leontyev (born 1940), Soviet Olympic gymnast Wassily Leontief (1905–1999), economist Russian-language surnames