Poljak is a surname. Notable people with the surname include:Allegra Poljak, Serbian professional footballer Eszter Poljak, Yugoslav sports shooter Maja Poljak, Croatian volleyball player Mateo Poljak, Croatian professional footballer Miroslav Poljak (1944–2015), Croatian water polo player Roberto Poljak (1932–2019), Argentine biophysicist and immunologist Stjepan Poljak, Croatian football midfielder Željko Poljak, Croatian basketball coach