She is known for her work with Gucci, L'Oréal, Next, Gap, Tommy Hilfiger, Victoria's Secret, Balmain Paris Hair Couture and Marks and Spencer.

Growing up in a banlieue district near Paris, which she describes as a "ghetto", Lenoir was first spotted at the age of 17 in 1997 when she was approached by a Ford booker in a post office.

[5] She signed with L'Oréal in 1997, and has since appeared in their advertisements alongside Laetitia Casta and long-term model and actress Andie MacDowell.

Lenoir was the face of UK high-street retailer Marks & Spencer, for four years until Christmas 2009[citation needed][6] and was seen in various British TV adverts, magazines and billboards alongside fellow models Erin O'Connor, Twiggy and Laura Bailey.

[12] On 9 May 2010, Lenoir was found unconscious, after a suspected suicide attempt in a park near her Paris home, by a man walking his dog.