Background: With recent improvements in endoscopic techniques and development of related equipment, endoscopic submucosal dissection (ESD) has become an established treatment for early gastric cancer (EGC). Currently, ESD is widely performed to treat elderly patients with EGC. However, the prevalence of comorbidities raises concerns of adverse events, which can cause severe deterioration in the overall condition of elderly patients. Thus, a consensus on the safety and efficacy of ESD is yet to be reached. Aim: To investigate the safety and efficacy of ESD in elderly patients by analyzing records of patients who underwent gastric ESD. Subjects and Methods: The subjects of this study were 235 patients (261 lesions) who underwent gastric ESD at our hospital between January 2006 and December 2016. The subjects were categorized into two groups: the non-elderly (NE) group comprising patients aged <79 years and the elderly (E) group comprising patients aged≥80 years. Treatment outcomes of the two groups were compared retrospectively. Results: Although no significant differences were observed in the overall incidence rate of adverse events between the two groups, more cases of pneumonia were observed in the E group (p=0.03) when analyzed according to disease type. No significant differences were observed in the rate of en bloc or complete resection; however, compared with the NE group, the rate of curative resection was significantly lower in the E group (p=0.03), and the procedure time for curative resection also was longer (p=0.03). No differences were identified in the length of hospitalization between the two groups. Conclusion: Although the risk of pneumonia should be considered when performing ESD in elderly patients with EGC, no difference was found in the overall incidence rate of adverse events. Thus, it is possible to perform ESD safety in this patient population.