Franciszek Andrzej Mazur (born Lewko Horodenko), also known as Stanisław Gajsler (August 1, 1895 – March 7, 1975) was a Polish lawyer of Ukrainian descent, a communist politician. President of the Supreme Court of the USSR (1926–1928), member of the Central Committee of the Communist Party of Poland (1930–1938). After 1945 he joined the Polish Workers' Party, then deputy member and member of the Politburo of the Central Committee of the Polish United Workers' Party (1948-1956). Member of the State National Council, the Sejm of the People's Republic of Poland of the 1st term, in the years 1952-