Dupasquier spent his early adult years as a pilot in the French Air Force, serving during the Algerian War. Following his discharge from the military, he studied engineering at the École catholique des arts et métiers, graduating in 1960.
Dupasquier was hired by Michelin's research division in 1962. He spent five years in research before transitioning to a commercial role, selling Michelin tyres to road car manufacturers. In 1973 he moved to the Competitions Department, the division responsible for Michelin's involvement in motorsport at the highest levels.
Dupasquier led Michelin's Formula One programme from 1977 to 1984, a period that coincided with the manufacturer's introduction of radial tyre technology to the sport — a development that proved transformative for Formula One tyre performance and prompted significant technical debate about the limits of grip and car behaviour.
Under his stewardship during this first era, Michelin secured four Formula One Constructors' and Drivers' championships. Jody Scheckter won the 1979 Drivers' title driving for Scuderia Ferrari on Michelin rubber — the first F1 world championship for the French manufacturer. Nelson Piquet subsequently claimed the championship twice with Brabham, and Niki Lauda secured the 1984 title with McLaren, also on Michelin tyres. These results established Michelin as a serious competitor to Goodyear, which had dominated F1 tyre supply through much of the preceding decade.
Michelin withdrew from Formula One at the end of the 1984 season.
Dupasquier led Michelin on their return to Formula One in 2001, once again heading the Competition Department through a new era of intense tyre competition, this time against Bridgestone. The return coincided with a period of significant regulatory change in Formula One and with the emergence of new teams and partnerships.
The 2005 season brought both triumph and controversy. Fernando Alonso won the Drivers' Championship driving for Renault on Michelin tyres — the first title for both Alonso and Renault in the modern era — while Michelin-equipped cars dominated the constructors' standings. However, the 2005 United States Grand Prix at Indianapolis became one of the most contentious races in Formula One history: following concerns over tyre safety on the banked Turn 13 section, all cars running Michelin tyres withdrew from the race before the start. Only the six Bridgestone-supplied cars competed, producing a result widely regarded as damaging to the sport's credibility.
Dupasquier retired from Michelin in 2005 at the end of this second Formula One programme.
Across his leadership of Michelin's Competition Department, the manufacturer accumulated 1,300 victories and 180 world titles in motorsport spanning Formula One, rally, endurance racing, and other categories. The scale of these results reflects both Michelin's investment in competition technology and Dupasquier's central role in directing that effort over more than three decades.
He was awarded the Legion of Honour in December 2006 in recognition of his services to French motorsport — one of the highest civilian distinctions in France. His career stands as a defining chapter in the history of tyre technology's influence on motorsport, particularly in Formula One, where tyre performance has repeatedly proven decisive to championship outcomes.