Abstract:Abstract: Objective?The study explored and summarized mucosal features of H. pylori gastritis, attempting to assess the clinical value of high-definition gastroscopy in diagnosing H. pylori infection.?Methods?From October 2016 to January 2017, 500 subjects were enrolled and examined with gastroscopy. Researchers made predictions according to mucosal features observed with high-definition gastroscopy and compared those with results of urea breath test to assess the accuracy.?Results?Features including diffuse gastric mucosal hyperaemia; mucosal edema; hypersecretion of gastric mucus; severe mucosal atrophy; intestinal metaplasia and duodenal ulcer suggested H. pylori infection, while regular arrangement of collecting venules; lack of atrophy; polyps and radiating gastric mucosal hyperaemia suggested uninfected status. The sensitivity, specificity, positive and negative predictive values of H. pylori infection was 90.1%, 70.4%, 71.0% and 89.9%, while the overall accuracy was 79.2%.?Conclusions?By observing typical mucosal patterns resulting from H. pylori infection, high-definition gastroscopy may become a reliable and efficient method of predicting H. pylori infection status in clinical practice.