Primary hyperparathyroidism is a rare disease of childhood. The condition is even rarer in the neonatal and infant stages. The disease, with its main manifestation-hypercalcemia-often is fatal. The authors successfully treated a 2.5-month-old boy who had primary parathyroid hyperplasia. The patient had recurrent pneumonia and failure to thrive. Blood test results showed an abnormally high level of calcium, which was resistant to medical therapy. Further investigations showed high levels of parathyroid hormone. The patient underwent neck exploration, which showed hyperplasia of the all four parathyroid glands. Total parathyroidectomy was performed, with one gland being autotransplanted to the deltoid muscle. The patient had an immediate hypocalcemic period, followed by normocalcemia. In light of the present case and others in the Literature, the authors recommended total parathyroidectomy followed by autotransplantation of a gland to an accessible muscle.