A gastric submucosal tumor in a 56-year-old man was presumed to be heterotopic pancreas on the basis of endoscopy and endoscopic ultrasonography. To obtain a histologic diagnosis we injected ethanol at the tumor site to create an artificial ulcer. This facilitated the removal of endoscopic biopsy specimens from the submucosal layer so that histologic examination could confirm the presence of heterotopic pancreatic tissue.