Patterns of chronic gastritis accompanied with other gastroduodenal diseases were studied histopathologically. Totally 220 cases of the resected stomach included 38 duodenal ulcer, 40 gastric ulcer, 87 early gastric cancer (34 undifferentiated and 53 differentiated type) and 55 advanced gastric cancer. Following results were obtained: 1) Degree of glandular atrophy and intestinal metaplasia increased as the patients became older. These mucosal changes spreaded usually from the antrum to the body. 2) Proliferation of lymph follicles and reactive cell-infiltration (lymphcytes, plasmacells, polymorphonuclear leucocytes and eosinophilis) were most frequently seen in the area of atrophic changes, and extended from the antrum to the body with increasing ages. 3) Fibrosis and hypertrophy of the muscularis mucosa increased with the progress of atrophic changes and also patient's year. 4) Atrophic changes were more prominent in the case of gastric ulcer than in the duodenal ulcer, if the patient's ages were same, and were also more significant in the case of differentiated type of early gastric cancer than in the undifferentiated type. Moreover, atrophic changes were not significantly different in the case of gastric ulcer and the undifferentiated type of early cancer, and also in differentiated early cancer and advanced gastric cancer. 5) In the antral mucosa, the degree of proliferation of lymph follicles and reactive cell-infiltration were most prominent in the case of duodenal ulcer, then gastric ulcer, undifferentiated type of early cancer and differentiated type. In the body-mucosa, these findings were seen in vice versa. 6) Fibrosis and hypertrophy of the muscularis mucosa, either at the antrum or the gastric body, were most significant in the case of differentiated type of early cancer, then gastric ulcer, undifferentiated type of early cancer and duodenal ulcer. 7) From these facts, the words of "Attendant Gastritis" seem to be unsuitable, because atrophic changes preced with developing various gastric diseases (ulcer, polyp and cancer). 8) From the findings of proliferation of lymph follicle, cell-infiltration, fibrosis and hypertrophy of the muscularis mucosa, these chronic gastritis seemed to be induced by inflammation.