The Sussex Senior Cup is an annual association football knockout cup competition for men's football clubs in the English county of Sussex; the winning team is presented with the Sussex Senior Challenge Cup, the county senior cup of the Sussex FA. For sponsorship purposes the trophy is also known as the Sussex Transport Senior Challenge Cup, after a new sponsorship deal was agreed in 2023.

The Sussex County Football Association, also simply known as Sussex County FA or Sussex FA, is the governing body of football in the county of Sussex, England. The Sussex County FA was founded on 23 September 1882 and run a number of County Cup competitions at various levels for teams all across the county. It is affiliated to The Football Association.