Persistent hyperinsulinemic hypoglycemia of infancy (PHHI) characterized by severe hypoglycemia caused by inappropriate over secretion of insulin is the most common cause of hypoglycemia in early infancy. The symptoms of hypoglycemia in neonate and infancy are neonatal sepsis, respiratory difficulty, tachypnea, apnea, cyanosis, and seizure. Especially the recurrent and severe hypoglycemia within $1^{st}$ year of life is responsible for severe and irreversible brain damage. To prevent it aggressive treatment is required. Due to severe and irreversible brain damage these children frequently require anesthesia during imaging procedures such as MRI or during various dental surgical procedures. Because of frequent hypoglycemia and dental phobia in children with neurologic disorder, anesthesiologists should pay attention to patient. We report a successful anesthetic management in a patient with PHHI for dental procedures.