Residual gastritis after gastrectomy brings the various symptoms such as abdominal pain, nausea, emesis and loss of appetite, and often hazards quality of life of the patient. Bile reflux to the stomach is believed as one of the important pathogenesis of residual gastritis, however the prevention for bile reflux cannot always heal the gastritis. Helicobacter pylori (H. pylori) is considered as one of the most important pathogenesis of gastroduodenal ulcer and gastritis, and H. pylori may possibly cause residual gastritis after gastrectomy. However, the association between infection with H. pylori and the residual gastritis has not revealed yet. In the present study, the association with H. pylori and the residual gastritis after gastrectomy was investigated in 56 patients who had undergone gastrectomy before. Twenty-four patients (42.9%) had H. pylori infection at their stomachs and the incidence of the infection in the patients with gastrectomy was significantly higher with subtotal gastrectomy. As for the histological gastritis score of Rauws (Rauws' score), Rauws' score of H. pylori positive group was significantly higher than H. pylori negative group. Furthermore, the eradication of H. pylori for the patients with serious symptoms of gastritis improved the symptoms and decreased significantly Rauws' score. These results suggest that H. pylori was associated with the pathogenesis of residual gastritis after gastrectomy.