Aleksei Fedorovich Filippov (Russian: Алексей Фёдорович Филиппов; 29 September 1923 – 10 October 2006) was a Russian mathematician who worked on differential equations, differential inclusions, diffraction theory and numerical methods. Born in Moscow in 1923, Filippov served in the Red Army during the Second World War, then attended Moscow State University (Faculty of Mechanics and Mathematics). After graduating in 1950, he remained to work at the school. He got his Ph.D. under the supervision of I. G. Petrovsky, and became a professor in 1978. He taught until his death in 2006.