Demoustier began his career in 2008, competing in the THP Spider Cup and the Mitjet Series. In 2009 he debuted in single-seaters, racing in Formula BMW Europe. In 2010 he began taking part in GT racing, contesting the FFSA GT Championship in an Aston Martin DBRS9 for the LMP Motorsport team, and co-driven by Grégory Guilvert. He also took part in the 24 Hours of Spa, finishing 21st in a Gulf Team First Lamborghini Gallardo LP560 GT3. He also raced in the final four rounds of the FIA GT3 European Championship, the first two in a Graff Racing Corvette Z06.R GT3 and the final two in a Team RosbergAudi R8 LMS.[1]
Demoustier began 2011 with a brief return to single-seaters in Formula Renault 2.0 Alps. He headed back to GT3 for the third round of the season, racing a Mercedes-Benz SLS AMG GT3 for Graff Racing. He took a podium at the season finale when he switched cars within the team to partner Mike Parisy, who claimed the series runner-up spot in the process.
The driver competed in the 2012, 2013 and 2014 Blancpain Endurance Series for ART Grand Prix with a McLaren MP4-12C, winning the 2014 Blancpain 3 Hours of Monza. In 2014 he also drove an ART McLaren at the European Le Mans Series.
In 2015 he remained in the Blancpain Endurance Series, switching to a Saintéloc Audi R8. Also, he drove a Chevrolet Cruze at the World Touring Car Championship. Demoustier returned to Saintéloc for the 2023 season, pairing with Christopher Mies in the Sprint Cup and joining Erwan Bastard and Paul Evrard in a Silver Cup entry for the Endurance Cup.[2]
Complete Formula Renault 2.0 Alps Series results
(key) (Races in bold indicate pole position; races in italics indicate fastest lap)
