(born 3 July 1979) is a French actress and model, who has appeared in 33 films since 1989. She was nominated for two César Awards for Best Supporting Actress in Swimming Pool (2003) and Un secret (2007).
In 2001, Sagnier was named one of the Shooting Stars by European Film Promotion. She was nominated for the César Award for Most Promising Actress in 8 Women (2002). She performed in two films in competition at the 2003 Cannes Film Festival, La Petite Lili and Swimming Pool, both released in the same year. Also in 2003, she won the Prix Romy Schneider.