The 2003–04 Irish Cup was the 124th edition of the Irish Cup, Northern Ireland's premier football knock-out cup competition. It concluded on 1 May 2004 with the final.
Coleraine were the defending champions, winning their 5th Irish Cup last season after a 1–0 win over Glentoran in the 2003 final. This season the same two clubs reached the final again. A 1–0 victory for Glentoran, who were appearing in the final for the sixth time in nine years was enough to seal their 20th Irish Cup win.[1][2]