A patient who had been supported with total parenteral nutrition (TPN) for over 8 years is herein presented, with emphasis on the changes observed in calcium metabolism. The patient was a 31-year-old female, who had undergone a subtotal jejunal and ileal resection for superior mesenteric artery occlusion. TPN was started soon after the surgery. She had been on TPN support for 105 months. Back pain developed at 97 months after the initiation of TPN. During her course, the serum calcium levels were judged to be within the normal ranges, while the 1 alpha, 25(OH)2Vit.D declined. Intermittent hypercalciuria was occasionally observed. Both the serum level of calcium and urinary calcium loss correlated closely to the amount of calcium infused, but they were not influenced by the amount of vitamin D (ergocalciferol) received. The serum level of parathormone and calcitonin were also within the normal ranges. The patient's vertebral bone, which was obtained at autopsy, revealed histopathological changes characteristic of osteoporosis. Based on the above, we conclude that a careful monitoring of the amount of calcium infused is called for to prevent bone disease in patients on long-term parenteral nutrition.