Rapidly progressive skin necrosis involving large areas of the skin associated with extensive vascular calcification was observed in a 39-year-old male patient on chronic hemodialysis. Histological examination of the periphery of a skin ulcer showed that subepidermal arterioles were occluded with fibrin deposits and that calcification was demonstrated in subcutaneous small arteries and arterioles. Electron microscopically, electron-dense materials, granular, crystal-like, vacuolar, or laminated, were found not only in arterial walls of the periphery of an ulcer but also, to a lesser extent, in those of normal-appearing skin. The skin necrosis gradually healed with antiseptic topical treatments and the injection of recombinant erythropoietin. The relationship between the vascular lesions in hemodialysis patients and progressive skin necrosis is not well known, although a combination of local and systemic factors may play an important role in the development of vascular calcification and skin necrosis in uremic and hemodialysis patients.