The 2003–04 Polish Cup was the fiftieth season of the annual Polish cup competition.
It began on 26 July 2003 with the preliminary round and ended on 1 June 2004 with second leg of the final, played at Stadion Wojska Polskiego, Warsaw.
Wisła Kraków were the defending champions.
The first legs took place on 30 September and 1 October, when the second legs took place on 21 and 22 October 2003.
Lech Poznań won 2–1 on aggregate