BACKGROUND/AIMS: Common endoscopic findings in stomachs with Helicobacter pylori infections include antral nodularity, thickened gastric folds, and visible submucosal vessels. These findings are suggestive but not diagnostic of H. pylori infection. Magnifying endoscopy can reveal more precisely the abnormal mucosal patterns in an H. pylori-infected stomach; however, it requires more training, expertise, and time. We aimed to establish a new classification for predicting H. pylori-infected stomachs by non-magnifying standard endoscopy alone. MATERIALS AND METHODS: A total of 617 participants who underwent gastroscopy were prospectively enrolled from August 2011 to January 2012. We performed a careful close examination of the corpus at the greater curvature maintaining a distance < or =10 mm between the endoscope tip and the mucosal surface. We classified gastric mucosal patterns into four categories: normal regular arrangement of collecting venules (numerous minute red dots), mosaic-like appearance (type A; swollen areae gastricae or snakeskin appearance), diffuse homogenous redness (type B), and mixed pattern (type C; irregular redness with groove) to predict H. pylori infection status. RESULTS: The frequencies of H. pylori infection in patients with a normal regular arrangement of collecting venules pattern and types A, B, and C patterns were 9.4%, 87.7%, 98.1%, and 90.9%, respectively. The sensitivity, specificity, and positive and negative predictive values of all abnormal patterns for prediction of H. pylori infection were 93.3%, 89.1%, 92.3%, and 90.6%, respectively. The overall accuracy was 91.6%. CONCLUSIONS: Careful close observation of the gastric mucosal pattern with standard endoscopy can predict H. pylori infection status.