Preoperative localization of ectopic parathyroid lesions is crucial for the correct treatment of patients with primary hyperparathyroidism. Invasive and noninvasive procedures, including selective venography, ultrasound, CT and MRI provide limited sensitivity in the detection of ectopic lesions. We report three patients in whom 99mTc-MIBI scintigraphy accurately detected ectopic parathyroid adenomas and was instrumental in the cure for these patients. Technetium-99m-MIBI scintigraphy provides a simple and accurate noninvasive test for the detection of ectopic parathyroid adenomas.