The Dutch designer will replace Ron Arad, who has been head of the department since 1998 and steps down in July.
Boontje was chosen from a shortlist of six. The other candidates included Jurgen Bey, Sebastien Bergne, Alexis Georgacopoulos, Maxine Naylor and Joseph Giacomin.
Boontje will continue to manage his own practice, Studio Tord Boontje.
picture Guy Drayton