We retrospectively reviewed 32 patients who underwent parathyroidectomy at our hospital for the last fourteen years. 1) Clinical appearance of primary hyperparathyroidism was in younger age in women. 2) In previous history or at the time of PTX, 9 patients had malignant tumors including 6 thyroid cancers, 36% of the patients with out bone related symptoms had a remarkable decrease in bone mineral content. 3) After PTX, none of patients had recurrent urolithiasis and bone mineral content of all patients was significantly increased in a short time. In addition, upper GI complaints were improved, or hypertension was partially normalized. However, renal insufficiency remained unchanged. 4) In preoperative localization study, Ultrasound sonography (US) demonstrated the best accuracy rate of 88% when only one gland was involved. US was able to detect multiple gland involvement only in 20% of 5 cases. 5) Hypercalciuria was recognized as one of the risk factors of stone formation in patients with primary hyperparathyroidism.