Pancreatic islet cell adenoma is a benign tumor of pancreatic beta-cell and a rare cause of hyperinsulinemic hypoglycemia in children. The authors experienced a case of pancreatic islet cell adenoma(Insulinoma)in a 11 year and 8 month old male who had frequent loss of consciousness and seizure. Enucleation was done after localization of tumor by selective celiac artery angiography and abdominal computed tomography. Diagnosis was confirmed by histologic findings as pancreatic-adenoma, gyriform growth pattern. A brief review of related literature was made.