The purpose of this study was to evaluate the biological features of gastric cancer of the remnant stomach (RSC). Twenty-one patients underwent resection of the remnant stomach for RSC and were divided into two groups: the RSCB group consisted of 11 patients who underwent distal gastrectomy for benign disease and the RSCM group consisted of 10 patients who underwent gastrectomy for primary gastric cancer. The interval between primary surgery and the appearance of gastric cancer in the remnant stomach was significantly shorter in the RSCM group than in the RSCB group. Invasion of adjacent organs was more frequent in the RSCM group than in the RSCB group and the Ki-67 labeling index of the tumors was significantly higher in the former group. Furthermore, p53 overexpression by tumors was almost twice as common in the RSCM group as in the RSCB group. Although there was no significant difference of the H. pylori positivity between the two groups, the rate for both groups was higher than reported in previous studies. Mutation of p53 may play an important role in the high proliferative activity of tumors in the RSCM group and H. pylori infection may be closely related to carcinogenesis in patients with RSC.