In the guideline, for H. pylori the Japanese Society of Helicobacter published diagnosis and treatment in July 2000. Only peptic ulcers and low grade MALT lymphomas are recommended as an indication of H. pylori eradication and other diseases such as atrophic gastritis, post EMR state for early gastric cancer and post-operated stomach due to gastric cancer, hyperplastic polyps and non-ulcer dyspepsia, were not included. In addition, Japanese social security foundation approves only peptic ulcers for indication of H. pylori eradication treatment. However, eradication therapy for atrophic gastritis should be considered in aspect of decreasing gastric cancer risk. Since accumulated epidemiological, experimental and clinical data strongly support its positive correlation with cancer risk, patients in high risk group for gastric cancer should be included for a target eradication therapy. Indication of the treatment should be expanded to histological gastritis caused by H. pylori in our country, where prevalence of gastric cancer is very high.