As of the 2015–16 season, the competition is called the RGB Senior Cup for sponsorship reasons. The reigning champions are Bodmin Town, who defeated Godolphin Athletic in the 2016 final to win the cup for the fifth time in seven years. It was Godolphin's second successive defeat in the final.
The competition was created in 1892 by the Cornwall County Football Association to provide a knockout tournament for the county's clubs. The inaugural tournament was won by Penzance in 1893. The competition didn't take place between 1915 and 1919 due to the First World War, and again between 1939 and 1945 due to the Second World War. In previous years, clubs were grouped together in earlier rounds due to Cornwall's geography, with a runner-up match being played alongside the final. This was discontinued in 1978, with the Cornwall Junior Cup taking its place. Both matches are played on Easter Monday at a neutral venue.
The Cornwall Senior Cup is contested by 52 clubs, as of the 2009–10 season, with seven rounds being played to decide the winner.
The preliminary round is made up of twenty-four clubs from the Cornwall Combination and East Cornwall League, played during the month of September. The first round is made up of the winners from the previous round and the clubs who received a bye, which takes place in October. The second round, played in December, is when clubs from the South West Peninsula League enter the competition, joining the eight winners from the previous round.
The third round is made up of sixteen teams, and the quarter-finals are made up of eight teams, with ties being played during the months of January and February respectively. The remaining clubs enter the semi-finals, which are played at a neutral venue in March, with the final being contested in April, again at a neutral venue.