Abstract: Medical records of infants and children evaluated for hypoglycemia, in the period January 1989 and December 2014, were retrospectively reviewed. Data included age, sex, maternal history, dietary history and drug intake, concomitant illness, clinical presentation, and results of relevant laboratory and radiological investigations. Glycogen storage disease, metabolic disorders, and hormonal disorders were excluded as recommended. Fifty-two patients were born in or referred to King Khalid University Hospital were evaluated. Wide spectrum of causes was noted with persistent hyperinsulinemic hypoglycemia of infancy (PHHI) in infants, while ketotic hypoglycemia was the commonest beyond infancy. The frequency and aetiological pattern of hypoglycemia is variable with persistent hyperinsulinemic hypoglycaemia of infancy (PHHI) was the commonest encountered in 10 (19.2%) infants, and while ketotic hypoglycemia was the most common cause of hypoglycemia in children beyond infancy found in 9 (17.3%) patients.