1920–21 Irish Cup

The 1920–21 Irish Cup was the 41st edition of the Irish Cup, the premier knock-out cup competition in Irish football.

Glentoran won the tournament for the 3rd time, defeating Glenavon 2–0 in the final at Windsor Park. This was the final tournament organised on an all-Ireland basis as the partition of Ireland process began in May 1921, and the FAI Cup was subsequently founded as an equivalent cup competition for teams in Southern Ireland (present-day Republic of Ireland).

First round

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Replay

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Quarter-finals

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Replay

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Semi-finals

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1Glenavon advanced into the final after Shelbourne refused to play on 17 March which was set as the semi-final replay date.