The case of a premature infant with the onset of hypercalcemia and apparent primary hyperparathyroidism in the immediate neonatal period is presented. Although the treatment in most such cases has been parathyroidectomy, this infant was managed medically and survived infancy without apparent complications. We believe her disorder represents the neonatal manifestations of familial hypocalciuric hypercalcemia. Her course supports the contention that this disorder may be self-limited in some infants and that appropriate medical management can preclude the need for surgical intervention in selected cases.