Heterotopic pancreas is a rare condition and its preoperative diagnosis is difficult. It is generally asymptomatic, but it may become clinically evident depending on the size, location and the pathological changes. Heterotopic pancreas can occur anywhere in the gastrointestinal tract, but most commonly is found in the antrum of the stomach. We report an unusual case of a 31-year-old male patient with gastric outlet obstruction and chronic pancreatitis caused by a submucosal tumor at the pre-pyloric area revealed at endoscopy. Distal gastrectomy was performed and a histological diagnosis of heterotopic pancreas was established. The patient had an uneventful postoperative course and remained symptom free in the follow-up of six months. The difficulty of making an accurate preoperative diagnosis is highlighted and a review of the literature on this pathology is hereby presented. Although heterotopic pancreas is rare, it should be considered in the differential diagnosis of pancreatitis and gastric outlet obstruction caused by a submucosal gastric tumor.