She decided to become a writer and director at the age of twelve after watching Ingmar Bergman's Sawdust and Tinsel, believing she had found her "fictional body" in Harriet Andersson's character, Anna.

[1] She started her career after studying acting at Yves Furet's "Studio d'Entraînement de l'Acteur" in Paris together with her sister, actress Marie-Hélène Breillat (born 2 June 1947) in 1967.

She made her film debut in Bernardo Bertolucci's Last Tango in Paris (1972) as Mouchette, a dressmaker, alongside her sister Marie-Hélène Breillat.

[6] After five months of hospitalization and a slow rehabilitation, she gradually returned to work, producing Une vieille maîtresse (The Last Mistress) in 2007.

In 2007, Breillat met notorious con man Christophe Rocancourt, and offered him a leading role in a movie that she was planning to make, based on her own novel Bad Love, and starring Naomi Campbell.

[13][14] It has been noted that "Breillat remains committed to the long take, particularly during scenes of sexual negotiation, a technique that showcases her performers' virtuosity as well as emphasizes the political and philosophical elements of sex.

[18] In August 2024 the actress Caroline Ducey, in an interview with the Nouvel Obs newsmagazine, accused Breillat of directing male actors to perform unsimulated sex acts upon her against her will during the filming of Romance.

Ducey stated that actor Reza Habouhossein later orally penetrated her in a cunnilingus scene at Breillat's command, despite her plea to the director "not to force me to do things I didn't want to."