Sport Page Handicap (1996) Mother Goose Stakes (1999, 2009) Saratoga Special Stakes (2003) Belmont Futurity Stakes (2003, 2005) Test Stakes (2003) Lafayette Stakes (2003, 2004) Lexington Stakes (2004) Ballerina Handicap (2004) Cowdin Stakes (2005) Kentucky Oaks (2005) Rebel Stakes (2007) Cowdin Stakes (2005) Arkansas Derby (2002,2007) Jockey Club Gold Cup(2007,2008) Pimlico Special(2008) Spinaway Stakes(2009) Haskell Invitational Handicap (2009) Woodward Stakes(2009) Vosburgh Stakes(2009) Cigar Mile Handicap(2009)

Steven Mark Asmussen (born November 18, 1965 in Gettysburg, South Dakota) is an American Thoroughbred racehorse trainer. Born into a horse racing family, his parents, Keith and Marilyn "Sis" Asmussen, are both trainers who operate El Primero Training Center off the Mines Road in Laredo, the seat of Webb County in south Texas. His older brother, Cash Asmussen, currently a trainer himself, is a retired Eclipse Award-winning jockey and a champion in Europe.

Asmussen began racing at age sixteen as a jockey, competing at racetracks in New Mexico, California, and New York for three years until his height and weight ended his riding career. In 1986 he began training Thoroughbreds and American Quarter Horses in New Mexico. In 2002, he led all trainers in Thoroughbred flat racing with 407 wins then in 2004 set a new record for wins by a trainer with 555, surpassing the previous standard of 496 held since 1976 by Jack Van Berg.