Hans Maass (German: Hans Maaß; June 17, 1911, Hamburg – April 15, 1992) was a German mathematician who introduced Maass wave forms (Maass 1949) and Koecher–Maass series (Maass 1950) and Maass–Selberg relations and who proved most of the Saito–Kurokawa conjecture. Maass was a student of Erich Hecke.