Abstract: Objective To study the endoscopy of heterotopic gastric mucosa in duodenal bulb and its pathologic features. Methods Clinical and endoscopic data about 102 patients with pathology-confirmed heterotopic gastric mucosa in duodenal bulb admitted to our hospital from October 2003 to October 2012 were retrospectively analyzed. Results The heterotopic foci were usually located on the anterior wall of duodenal bulb and could be divided into granular hyperplasia type (in 35 patients), flat elevated type (in 20 patients) and polypoid hyperplasia type (in 47 patients) according to their endoscopic findings. Pathological examination showed gastric body glands, fundic glands or pyloric glands in the lamina propria. Conclusion Polypoid hyperplasia is the most common type of heterotopic gastric mucosa in duodenal bulb with a low diagnostic accuracy of endoscopy. Histopathology plays an important role in its diagnosis.