Mark Isherwood (born January 31, 1989) is a Canadian retired ice hockey defenceman. Isherwood played four seasons (2006-2010) of major junior hockey with the Medicine Hat Tigers of the Western Hockey League, scoring 128 points and registering 353 penalty minutes in 268 games played. During his rookie 2010–11 ECHL season with the Alaska Aces, Isherwood was a member of the Kelly Cup championship team, and he led all ECHL defensemen with 15 goals and 11 power-play goals. He was recognized for his outstanding play by being named to the ECHL All-Rookie Team.