Mark Warkentin (born November 14, 1979) is an American open water swimmer and swimming coach.

Warkentin qualified for the 2008 Summer Olympics in Beijing following his performance at the 2008 Open Water World Championships.

"[1] He is a two-time national champion in the open water 25-kilometer, the longest sanctioned race in the sport.

[3] Warkentin finished in eighth place with a time of 1:52:13.0,[4] just twenty-one seconds behind winner Maarten van der Weijden.

[5] Warkentin became head coach of the Santa Barbara Swim Club on December 1, 2012, returning to lead his childhood team.