Fifteen patients with 16 histologically verified heterotopic pancreas lesions were encountered at our department during a period of 22 years. The incidence was 0.25% of the findings of all abdominal operations during the same period. Heterotopic pancreas caused symptoms in 5 patients. All the remaining 10 patients were asymptomatic, whose lesions were found coincidentally at the time of surgery for other abdominal diseases. Heterotopic pancreas developed most frequently in the jejunum (46.7%). Preoperatively, only 2 lesions of the stomach in 2 patients were suspected to be heterotopic pancreas. At the time of operation, 10 of 16 lesions were diagnosed correctly on the basis of the macroscopic features. Malignant degeneration was seen in the duodenal and jejunal heterotopic pancreas. The former lesion was successfully resected by pancreatoduodenectomy. There were no deaths related to heterotopic pancreas or to the operations performed. Resection of the tissue-bearing area is advisable when the condition is encountered coincidentally at operation, and surgical exploration should be done for all symptomatic patients, particularly in the absence of histological diagnosis.