The black full-length coat with wool fringe was designed for Bardot by Jean Bouquin in the 1960s, during the peak of the actress’s success.
It is embroidered with butterflies and comes with signed photographs and a dedication by Bardot.
Low said: “Jean Bouquin’s designs were extremely popular among the Saint-Tropez jet set in the 1960s – closely associated with Bardot’s bohemian look and ‘hippie chic’.”
Bouquin’s designs were influential during the 1960s and are sometimes described as “hippie deluxe”. After opening his boutique, he designed for many stars included Mick and Bianca Jagger, Jane Birkin and Natalie Wood.
The auction will begin at 10:00 BST on Tuesday.
