Secondary hyperparathyroidism is the condition is which parathyroid hormone(PTH) is over secreted to compensate for a chronically low serum calcium level and chronic renal failure is the most common cause. In 1934, Albreight reported an association between hyperparathyroidism and the chronic renal failure and in 1960, Stanbury first reported subtotal parathyroidectomy for the treatment of secondary hyperparathyroidism. The physiologic mechanism leading to secondary hyperparathyroidism in the chronic renal failure are well known and relatively well controled with medical management, but sometimes may necessitate surgical intervention in medically intractable cases. In Korea, the surgery for secondry hyperparathyroidism is not frequently performed yet as in western countries. We experienced two cases of secondary hyperparathyroidism recently and report its results of subtotal parathyrodiectomy.