Gaspard Ulliel is revealed in 2002 by Michel Blanc who gives him a role in his choral comedy Embrassez qui vous voudrez. This role earned him the prize for Most Promising Actor at Les Lumières de la Presse Étrangère that year. Ulliel was nominated twice for a César award for Most Promising Actor in 2003 and 2004. But it was the third time that Ulliel won the award in 2005 thanks to Jean-Pierre Jeunet's A Very Long Engagement, in which he played alongside Audrey Tautou. Les Lumières de la Presse Étrangère awarded him a second time in 2015 for his title role in Bertrand Bonnello's Saint Laurent before the César Academy gave him the statuette of the best actor in 2017 for his role in Just the End of the World by Canadian Xavier Dolan.
In his 20-year career, Gaspard Ulliel has had 20 million admissions in cinemas and has acted for the greatest: from Christophe Gans to Gus Van Sant, including André Téchiné, Bertrand Tavernier and Justine Triet.
Gaspard Ulliel came to Les Arcs Film Festival in 2019 for the special screening of Guillaume Nicloux's (president of the jury) film To the Ends of the World in which he plays the lead role.