Abstract: Objective To evaluate the efficacy and toxicity of S-1 for elderly patients with gastric cancer after radical surgery. Methods After D2 radical surgery， 52 cases of elderly gastric cancer were divided into 2 groups randomly. Twenty-six cases were treated by S-1（S-1 40-60mg po，twice a day，d1-d28， 6 weeks was one cycle） as treatment group. The another 26 cases were treated by FOLFOX 4（oxaliplatin 85mg／m2 iv，d1；calcium folinatc 200mg／m2，iv 2h，d1-d2；5-FU 400 mg／m2 iv，d1-d2；5-FU 600 mg／m2，civ 22h，d1-d2，14 days was one cycle）as control group. Curative effects and toxicities were compared between the two groups in the following 2 years. Results All 52 patients were received 6 months’ adjuvant chemotherapy. The 1-year survival rates in treatment and control group was 69.23％ and 61.54％，respectively（P＞0.05）.The 1-year relapse-free survival rates in two groups was 53.85％ and 57.69％，respectively（P＞0.05）. The 2-year survival rates in treatment and control group was 34.62％ and 38.46％，respectively（P＞0.05）. The 2-year relapse-free survival rates in two groups was 30.77％ and 23.08％，respectively（P＞0.05）. Incidence rates of nausea， emesis， diarrhea and PN toxicity were remarkably lower in treatment group than those in control group（P＜0.05）. Conclusion After D2 radical surgery， curative effects of S-1 is similar to FOLFOX 4 for elderly gastric cancer patients and S-1 has less toxicities.