A case of asymptomatic pancreatic islet cell tumor (glucagonoma) is reported. A 36-year-old woman undergoing a ultrasonic scan was found to have two masses in the body and tail of the pancreas measuring 5 cm and 4 cm in diameter, respectively. Investigations of serum peptide hormones revealed an elevated glucagon level of 27,500 pg/ml (normal < 100 pg/ml), suggesting the possibility of an islet cell tumor (glucagonoma). The patient, however, was asymptomatic although high levels of glucagon were present. The patient underwent distal pancreatectomy to remove the lesions in the body and tail of the pancreas. Histological findings revealed islet cell tumors of the pancreas, and immuno histochemical staining of the tumor cells demonstrated a positive reaction for chromogranin and glucagon.