We herein describe a case of somatostatinoma coexisting with a gastrointestinal stromal tumor (GIST) in the duodenum of an 81-year-old woman with Von Recklinghausen's disease (VRD) and common bile duct stone who presented with diarrhea of three months in duration. Gastroduodenoscopy revealed an ulcer on the second part of the duodenum. A 2.1-cm enhancing tumor was observed to extend from the ulcer on an abdominal computed tomography scan. Subtotal stomach-preserving pancreaticoduodenectomy revealed a somatostatinoma on the papilla of the vater and duodenal GIST. There have been only eight reports on VRD associated with ampullary somatostatinoma and GIST. An awareness of this possibility in patients with gastrointestinal lesions is necessary for proper treatment and patient management.