|Over the past few years, the profile of Helicobacter pylori infection has changed in Japan. In particular, the relationship between H. pylori and gastric cancer has been demonstrated more clearly. In 2016, the committee of the Japanese Society for Helicobacter Research has revised the guidelines for diagnosis and treatment of H. pylori infection in Japan. In 2013, Treatments for H. pylori-associated gastritis was covered by health insurance. In fact, all H. pylori-infected patients in Japan can receive these insurance-covered combination therapies for the eradication. Before diagnosing and treating H. pylori infection, an endoscopic examination is required to obtain a definitive diagnosis of H.pylori gastritis.Successful eradication of H. pylori improves histological gastritis and may prevent various diseases associated with H. pylori infection, such as gastric/duodenal ulcer and gastric cancer. Recently, we have a newly developed potassium-competitive acid blocker (PCAB), Vonoprazan, and triple therapy containing PCAB has better efficacy than PPI-containing eradication therapy. It is necessary to evaluate the risk of gastric cancer by endoscopic findings, and also necessary to make a long follow-up after the eradication. Especially for atrophic gastritis, intestinal metaplasia, enlarged fold, and nodular gastritis, which are considered as being in a high-risk group of gastric cancer, and endoscopic diagnosis of them is undeniably required. Improvements of them after the eradication may be regarded as one reason for prevention of gastric cancer. We attempt to score for these findings according to the grades of the lesions.