The authors report a rare case of persistent hyperinsulinemic hypoglycemia of infancy (PHHI) with congenital neuroblastoma without feature(s) of Beckwith-Wiedemann syndrome. A term newborn with a birth weight of 3,900 g developed hypoglycemia one hour after birth and required up to 20 mg/kg/min of intravenous glucose infusion to maintain euglycemia. Investigations during the critical period revealed an inappropriately high insulin level. An abdominal CT scan revealed a normal pancreas, right suprarenal mass, and liver nodules. A condition of stage 4S neuroblastoma was suspected and supported by an increased ratio of urine vanillylmandelic acid to creatinine. The bone marrow smear was normal. She underwent near total pancreatectomy at the age of 2 months. The suprarenal mass and liver nodules were not found during the operation or during repeated abdominal CT scans at 3 month of age. Spontaneous regression of neuroblastoma was suspected. The pathology of the pancreas was compatible with PHHI.