A native of France and the son of the late jockey-turned-trainer Robert Leparoux, he has risen to prominence since beginning his riding career in 2005. He won the Eclipse Award as the outstanding apprentice rider of 2006, when he led the nation with 403 victories, and a second Eclipse in 2009 as the outstanding jockey. After spending two years as an exercise rider for trainer Patrick Biancone, he made his debut as a jockey at Saratoga. He won six races on a single racing program at Churchill Downs in 2007 and won three Breeders' Cup races in 2009. In 2011, he was sixth in purse money earned by a jockey in North America with $13,874,620.
Leparoux was in the irons to pilot Java's War to a 14th place finish in the 2013 Kentucky Derby, and then picked up Vyjack as a mount for the Belmont Stakes.