The oral active vitamin D pulse therapy was performed for 20 chronic hemodialysis patients with secondary hyperparathyroidism (2 degrees HPT). Before pulse therapy, all patients showed high-turnover bone diseases, elevated serum alkaline phosphatase (Alp) and elevated serum parathyroid hormone (PTH). They had at least one parathyroid gland detected by ultrasonography. In one patient, serum PTH level did not decrease during three months. In five patients, hypercalcemia was observed so that the pulse therapy was with drawn. Another patient was resistant to the second pulse therapy for recurrence of 2 degrees HPT. Total parathyroidectomy and autotransplantation was performed in these seven patients. The size of parathyroid gland in patients undergoing surgical treatment was significantly larger than those estimated by ultrasonography in patients successfully treated with pulse therapy (p < 0.005). In all patients with surgical treatment, the conventional oral active vitamin D therapy was performed with caution to hypercalcemia preoperatively. The preoperative Alp levels decreased compared with those of at the beginning of the pulse therapy. Postoperatively, the total amount of intravenous administered calcium decreased, and serum calcium levels were easily controlled.