Mark R. Frostad (born January 19, 1949 in Brantford, Ontario) is a Canadian Thoroughbred horse trainer. He grew up with a father who owned a stud farm but before becoming involved in thoroughbred horse racing, Frostad obtained a BA degree in literature from Princeton University then in 1976 an MBA degree from the University of Western Ontario in London, Ontario,.
In 1991 he became actively involved in racing as a Thoroughbred trainer, meeting with great success in the employ of Sam-Son Farm whom he joined in 1995. Among his more than 100 stakes race victories, he won Canada's most prestigious horse race, the Queen's Plate, in 1996, 2000,2001 and 2009 and both the Canadian International and the Breeders' Cup Turf in 1997.
Frostad has won the Sovereign Award for Outstanding Trainer three times. His significant horses include Quiet Resolve, Chief Bearhart, and Soaring Free, all winners of the Sovereign Award for Canadian Horse of the Year.
Mark Frostad has a wife, Pam Frostad, and three children, Kate, Justine, and Peter.