Miguel Martinez has signed a three-year contract beginning in 2009 with the Felt-International team.
The 2000 Olympic Games mountain bike gold medallist decided to return full-time to the dirt after racing on the road for the past few seasons.
"I have signed an important contract," said Martinez. "The next four years will allow me to concentrate to me on my objective, to participate in the London Olympic Games with the ambition of winning another medal."
The 32 year-old French racer twice won the World Championship and the World Cup. He switched to the road in 2001 and raced the Tour de France. He first returned to the dirt in 2004 at the Roc d'Azur.
"My 2008 season wrapped up in a good way," he said. "I finished the Roc d'Azur within four minutes of the winner although I did not have good preparation."
He added: "The team has quickly made a good impression on me. They are all motivated and have asked me to help the younger riders."