Recently, thanks to the collected knowledge and increased diagnostic abilities we more often meet the diseases that have been considered very seldom. Beside that, we form the new assumptions that must be proved. Today, more often we meet gastric mucosa in duodenum. That according to some researchers, introduces a real possibility for appearance of the polyps, ulcers or cancer on gastric substratum. In the subject patient the two polyps of the gastric origin were found in a duodenum. That could support the assumption that ectopic gastric mucosa presents one of the real possibilities for appearance of polyps, ulcers and cancer.