The Honourable Daphne Diana Joan Susanna Guinness (born 9 November 1967) is a British and Irish fashion designer, art collector, model, musician, film producer and actor. She is an heir by direct descent of the 18th century Irish brewer Arthur Guinness.
Her father is Jonathan Guinness, 3rd Baron Moyne, the eldest son of Diana Mitford Mosley and Bryan Guinness. Diana Mitford was the daughter of David Freeman-Mitford, 2nd Baron Redesdale, the father of the Mitford sisters. Mitford divorced Guinness and married the leader of the British Union of Fascists, Sir Oswald Mosley. Daphne Guinness has said she did not know of Mosley's political affiliations, before she heard in 1980 on the BBC News that he had died.