Samuel Dumoulin (born 20 August 1980) is a retired French professional road bicycle racer, who last rode for UCI WorldTeam AG2R La Mondiale.
Dumoulin was a professional from 2002, for the Jean Delatour team.
At the end of 2003 he moved to AG2R Prévoyance before riding for Cofidis.
Dumoulin left Cofidis at the end of the 2012 season, after five seasons with the team, and signed an initial two-year contract with Ag2r–La Mondiale for the 2013 and 2014 seasons.
He remained with AG2R La Mondiale until his retirement at the end of the 2019 season.