Background The strategy for treating extremely aged patients with gastric carcinoma is controversial. This study reviews the prognoses of patients aged 85 years and older who were diagnosed with gastric carcinoma. Methods One hundred seventeen patients aged 85 years and older were diagnosed as having gastric carcinoma after 1969 in our institution. After excluding those at stage IV, 36 cases underwent curative resection and 30 cases received best supportive care (BSC), which we reviewed retrospectively. Results Surgical methods included distal gastrectomy for 28 cases, total gastrectomy for five cases, and other procedures for three cases. Postoperatively, pneumonia developed in four cases, anastomotic leakage in two cases, and pancreatic fistula in one case. Two patients died of pneumonia within 1 month of surgery. Univariate analysis demonstrated that age, surgery, performance status, and sodium level were statistically significant prognostic factors. Multivariate analysis demonstrated that surgery was the only independent prognostic factor. When patients with a performance status of 4 were excluded, the clinical characteristics of the surgery group (n = 36) and BSC group (n = 20) were statistically identical, and the overall survival was significantly better in the surgery group (p = 0.0078).Conclusions Postoperative outcomes were relatively acceptable. Surgery may be feasible and beneficial even for extremely aged patients 85 years and older, except for those with a performance status of 4.