Idiopathic avascular necrosis of the capitate is a very rare condition. Only 7 cases have been reported until 2002 in the literature since the lesion was originally described by Jonsson in 1942. The incidence of the injury has not been documented and no report has been issued in Korea. The author experienced one case of idiopathic capitate avascular necrosis which was treated by curettage and autoiliac bone graft.