The works were collected by German-born photographer Gunter Sachs, best known for his playboy lifestyle and brief marriage to French actress Brigitte Bardot. He committed suicide at the age of 78 in May 2011.
Sachs had collected hundreds of art works over his lifetime and was friends with many key artists of the 20th century, including Warhol, Dali and Georges Mathieu.
Warhol's portrait of Bridget Bardot, Sachs' second wife, is one of the works being auctioned. A white plaster bust of Bardot by Alain Gourdon also is for sale.
Sotheby's will auction the 300 pieces on Tuesday and Wednesday, and it expects them to fetch more than 20 million pounds ($32 million).
Sachs made his name as a photographer, documentary filmmaker and art collector. He lived a jet set lifestyle, spending time with top artists in Paris and New York.
Oliver Barker, a contemporary art specialist at Sotheby's, said: "Gunter's unique contribution was his sex appeal, his handsome good looks," and his "the promotion of American art in Europe in the 1970s."