Mark Andreas Cornelis Versfeld (born June 13, 1976) is a former backstroke swimmer from Canada. At the 2000 Summer Olympics he finished in 26th position in the 100 m backstroke. He won the same event and the 200 m backstroke two years earlier, at the 1998 Commonwealth Games. At the 1998 Aquatic World Championships he won a silver in the 100 m backstroke and bronze in the 200 m backstroke, breaking a Commonwealth Record in the process. He was named Canadian Male Aquatic Athlete of the Year in 1998.
Two years after his birth, his family moved to Fort McMurray where he started swimming in a club at age 8. In 1981 his family relocated to Edmonton, and three years later to Calgary. After departure of his Calgary coach Deryk Snelling, Versfeld moved to Vancouver, where he trained with Tom Johnson and studied psychology and political science at the University of British Columbia.