Background: Primary hyperparathyroidism remains one of the leading causes of hypercalcemia in the world today. To plan the appropriate surgery with the least morbidity for the patient, preoperative localization of the abnormal parathyroid gland is necessary. Tc99m sestamibi scintigraphy and ultrasonography are the two main modalities for imaging the parathyroid glands.   Patients and methods: This prospective interventional non-randomized non-controlled study was conducted in the Department of General Surgery at Ain Shams University hospitals in the period from April 2013 to October 2016 on thirty patients (7 males and 23 females) with primary hyperparathyroidism. Informed consent was obtained from all patients included in the study.   Results: Out of thirty patients, the combined preoperative ultrasonography and Tc99m sestamibi scintigraphy was accurate in twenty eight patients (93.33%) while they could not identify the pathological gland in two patients (6.66%). Accuracy of ultrasonography alone was 76.66% (23 patients), while accuracy of T99m sestamibi scan alone was 86.66% (26 patients).   Conclusion: The preoperative combination of ultrasonography and Tc99m sestamibi scintigraphy is effective with high accuracy in predicting the location of abnormal parathyroid gland(s) in patients with primary hyperparathyroidism.