Hypercalcemia may occur in approximately 15% of children with the Williams-Beuren syndrome. The episodes of hypercalcemic crisis usually respond well to initial hyperhydration, loop diuretics and calcitonin, bisphosphonates, or subsequent dialysis. However, many patients suffer from recurrent or persistent hypercalcemia after the resolution of the hypercalcemic crisis. Although hypercalcemia in the Williams-Beuren syndrome is generally considered transient, it may last for several months, result in significant morbidity, and compromise physical growth. There are no guidelines for the management of persistent or recurrent hypercalcemia in patients with the Williams-Beuren syndrome. In this report, we describe our experience of conducting oral corticosteroid therapy in a child with the Williams-Beuren syndrome who continued to have hypercalcemia after the resolution of the hypercalcemic crisis.