Hypoglycemia is a frequent problem in infants and children, causing a significant dilemma to reach the correct diagnosis and perform the appropriate management. Congenital hyperinsulinism is the most common cause of hypoglycemic hyperinsulinemia in infants and is due to beta-cell hyperplasia caused by genetic defects. This is a well-known genetically and clinically heterogeneous condition causing severe hypoglycemia in infants. Insulin-secreting tumors (insulinoma) are rare findings during childhood. In contrast, insulinoma is the most common form of endogenous hypoglycemic hyperinsulinemia in the adult population. Here we present a successful diagnosis and treatment of a nine-year-old Saudi child who presented for the first time with severe episodes of hypoglycemia at age seven. Critical samples at the time of hypoglycemia confirmed the associated hyperinsulinemia state. Initially, the child responded well to anti-insulin medications at small doses, but with time the disease became progressive in severity requiring a high dose of anti-insulin medications, frequent glucagon injections, and hospital admission for intravenous dextrose infusion. After two years of seeking therapy in many hospitals, the final diagnosis was confirmed to be an insulinoma, which was removed surgically, resulting in a complete cure and full recovery. Here we report the first published case of insulinoma in a young child aged < 15 years old in Saudi Arabia, their disease course, final diagnostic steps, and curative therapy. We conclude that hypoglycemia in children is challenging in terms of diagnosis and management. Although insulinoma is very rare in children, it requires significant time and effort by a pediatrician, pediatric endocrinologist, patients, and parents to reach the final diagnosis and carefully preserve the integrity of the neurological state of those children. The OMJ is Published Bimonthly and Copyrighted 2020 by the OMSB.