Currently, many international guidelines recommend Helicobacter pylori (H. pylori) eradication in patients with precancerous lesions such as atrophic gastritis (AG) and intestinal metaplasia (IM). However, there are still many controversies in whether H. pylori eradication improves AG and IM. Taking the results of related studies together, it seems likely that H. pylori eradication improves AG to some extent. However, a dominant opinion is that IM which progressed to a certain level is already an irreversible status (point of no return). Therefore, in order to obtain an optimal effect for gastric cancer prevention, eradication of H. pylori in the earlier and reversible stage of AG and IM is recommended.