(born October 24, 1973 in Butte, Montana) is an American professional road bicycle racer who rides with UCI ProTeam Astana. He previously rode for Discovery Channel, Gerolsteiner, and Rabobank. In 2010 he will ride for Team Radioshack.
His major results are 1st overall in the 2009 Tour of California (winner of Stage 6 time trial), the 2008 Tour of California (winning the Stage 5 time trial), 2nd overall in the 2008 Vuelta a España (winning two stages), 1st overall in the 2007 Tour of California (winning the Prologue and Stage 5 time trials), 1st overall in the 2006 Dauphiné Libéré, 1st overall in the 2005 Deutschland Tour, 3rd overall in the 2001 Vuelta a España, and four top-ten finishes in the Tour de France general classification, including 3rd overall in 2007. He lives in Santa Rosa, California with his wife Odessa Gunn, though during the cycling season he primarily lives in Gerona, Spain. Leipheimer won the 2007 USA road championship, 1:11 seconds ahead of Discovery team mate and defending champion George Hincapie.
Leipheimer won the bronze medal at the 2008 Beijing Olympic Games in the road time trial.