The private show marks the 40th anniversary of the house and will raise money for charity.
Pictures of British designer Gina Fratini and her creations, including Princess Diana’s dress.
“Diana: Her Fashion Story,” which opens to the public on Feb. 24, showcases looks she wore during daytime public engagements as well as for evening occasions.
The show will mark 20 years since Diana’s death in Paris.
Duke and Duchess of Cambridge open Kensington Palace for event.
Palace says little prince is now the number-one target for photographers.
Fashion figures, royals host parties in east and west London.