Objective:To explore the diagnosis and treatment of primary hyperparathyroidism (PHPT). Methods:Clinical data of 35 cases of PHPT were retrospectively analyzed. Results:23 out of 26 cases (88.5%) undergoing preoperative ultrasonography with a positive result were verified by intraoperative findings. For ECT, the positive rate was 21 out of 23 cases (95.5%). Unilateral neck explorations (UNE) was performed in 27 cases of parathyroidoma. Two cases of parathyroid hyperplasia were treated by UNE and the other two cases by bilateral neck exploration (BNE). The procedure for 3 cases of parathyroid carcinoma was the same as that for papillary thyroid carcinoma. Unilateral resection of thyroid and parathyroid was done in a case of parathyroidoma with malignant change. Emergency excision of parathyroidoma, after emergency medical management, was performed in a patient with parathyroid storm, and the symptoms subsided postoperatively. All cases developed hypocalcemia in various degrees after surgery, but the symptoms were relieved with the use of calcium gluconate. Conclusions:PHPT could be diagnosed according to coelevated calcemia and PTH. Ultrasonography and ECT should be considered as the methods of first choice for preoperative localization. UNE of parathyroidoma could be feasible if accurate image localizations are available. Radionuclear guided parathyroid resection could be performed in the patients with ectopic parathyroid disease or lesions without accurate localization. Aggressive surgical exploration after medical control of symptoms is the first choice of treatment when parathyroid storm is diagnosed.