It began on 27 October 1990 with the first preliminary round and concluded on 9 June 1991 with the final which was held at Makario Stadium.
Omonia won their 9th Cypriot Cup trophy after beating Olympiakos Nicosia 1–0 in the final.
In the preliminary rounds each tie was played as a single leg and was held at the home ground of one of the two teams, according to the draw results.
If both teams had scored the same number of home and away goals, then extra time was following after the end of the second leg match.
If there weren't scored any goals during extra time, the qualifying team was determined by penalty shoot-out.