Purpose: Among patients with gastric cancer who underwent radical gastrectomy, the proportion of patients aged ≥80 years has increased. This study aimed to evaluate surgical outcomes and survival of patients aged ≥80 years who underwent curative resection for gastric cancer and identify independent factors that affect postoperative survival. Methods: This retrospective study enrolled 1,066 patients aged ≥65 years with gastric cancer who underwent curative resection between January 2014 and December 2018 at a single institution. They were divided into those aged ≥80 years (old-elderly group) and 65–79 years (young-elderly group). Their clinicopathological characteristics and surgical outcomes were compared. Results: Of the 1,066 patients, 136 (12.8%) were 80 years or older. Higher American Society of Anesthesiologists (ASA) physical status classification and more advanced cancers were observed in the old-elderly group than in the young-elderly group. No significant difference in postoperative complications was found between the groups. At a median follow-up of 49.1 months, the 5-year overall survival rate after surgery for the old-elderly group was lower than that for the youngelderly group (75.6% vs. 87.0%, P < 0.001). However, the 5-year disease-specific survival rate was comparable between the groups (90.1% vs. 92.2%, P = 0.324). ASA physical status classification, pathologic stage, and surgical approach were independent predictors of overall survival. Conclusion Old-elderly patients aged ≥80 years had comparable postoperative outcomes and disease-specific survival to the young-elderly group, suggesting that curative gastrectomy can be considered a viable option for octogenarian patients with gastric cancer.