After rising through the ranks of the academy, he was promoted to the club's first team for the 2006–07 season, and signed his first professional contract with the side. A technically blessed, ball-winning box-to-box midfielder, Chantôme made his debut for Paris Saint-Germain as a 75th-minute substitute against Lyon in the Trophée des Champions, which the club lost 5–4 in a penalty shootout following a 1–1 draw in 120 minutes of play. He made his league debut for the club as an 83rd-minute substitute in a 1–0 win against Valenciennes on 12 August 2006.
As he progressed through the academy, Chantôme was elevated to the first team for the 2006–07 season and signed his initial professional deal with the club. A technically skilled, ball-winning midfielder who excelled in both defense and attack, Chantôme entered the field as a substitute for Paris Saint-Germain against Lyon in the Trophée des Champions, which the club ultimately lost after a penalty shootout following a 1–1 draw. He made his league debut for the club by coming on as a substitute in a 1–0 win over Valenciennes on August 12, 2006.