The 2005 Porsche Carrera Cup Great Britain was the third season of the one-make championship. It consisted of 20 rounds, beginning on 9 April at Donington Park and finishing on 2 October at Brands Hatch. The series supported the British Touring Car Championship throughout the season. Damien Faulkner claimed his first title, ahead of Richard Westbrook who had won the championship the previous year.