The 31-year-old actress is seen leaning against a chaise lounge to promote the new lipstick range, reported Daily Mail online.
Portman is no stranger to appearing naked for the French fashion house.
Previously, she shot for Miss Dior Cherie Fragrance in which she posed naked from the waist up, with just her hands covering her up.
The new advertisement is the first Portman has appeared in since John Galliano was fired from Dior after going on an anti-Semitic rant in Paris.
The actress publicly denounced it, saying she was deeply saddened and shocked by the designer's actions.
Galliano was subsequently replaced by former Jil Sander creative director Raf Simons.
