A newborn with important signs of fetal disturbance and respiratory distress developed plaques on both buttocks 14 days after birth with the clinical and histological characteristics of subcutaneous fat necrosis of the newborn. Fifteen days after the onset of the cutaneous signs, a discrete degree of hypercalcemia was detected. Its outcome was favorable due to the early establishment of a diet rich in medium-chain triglycerides and devoid of calcium and vitamin D. Sixteen cases of idiopathic hypercalcemia in newborn with subcutaneous fat necrosis have been reported of which 3 died. Serial serum calcium determinations should be made in such infants and they should be observed closely for signs and symptoms of hypercalcemia.