A 46-year-old male patient underwent long-term hemodialysis treatment had suffered from calciphylaxis (defined by Selye), such symptoms as advanced systemic vascular calcification, rapid progression of gangrene on both fingers and toes, disturbance of consciousness, and sclerosis and obstruction of the superficial vein after venipuncture during 11.5 years of dialysis. Furthermore, he had a long history (30 years) of heavy smoking. He died as a result of sepsis due to pneumonia after 12.5 years of dialysis. He had received dialysis treatment using a small amount of dialysate (50 liters on a recirculating system) for 8.5 years and had been dialysed 2 and 2 or 3 times a week for 10 years. As a result of this insufficient dialysis treatment, his characteristic laboratory data showed hypocalcemia, hyperphosphatemia, elevated calcium-phosphorus product, advanced metabolic acidosis, hyperalkaliphosphatemia and elevated serum parathyroid hormone. Autopsy revealed the following: 1) enlargement parathyroid gland enlarged in two (4.0 g and 2.0 g, respectively) showing adenomatous hyperplasia presenting cord-like arrangement of chief cells and water-clear cells, 2) systemic medial calcification in radial, ulnar, renal, mesenteric and brain arteries, and 3) Berline-blue positive iron deposit in calcified arteries in mesenteric and parathyroid tissue. From these results, we concluded that factors (challengers) related to the appearance of calciphylaxis might be as follows: 1) advanced secondary hyperparathyroidism, 2) long-term uremic state, 3) administration of VD2 and VD3, 4) iron salt injection, and 5) a long history of heavy smoking. We speculated that these challengers might act synergistically to cause calciphylaxis.