AIM: To rationally evaluate the effect of S-1 vs capecitabine for the treatment of gastric cancer.METHODS: MEDLINE, EMBASE, Cochrane Controlled Trials Register, Google Scholar, and China Journal Full Text Database were accessed to collect clinical randomized controlled trials regarding the effect of S-1 vs capecitabine for the treatment of gastric cancer patients.Statistical analysis was performed by metaanalysis.Four randomized controlled trials met the inclusion criteria.RESULTS: Compared with capecitabine regimens, the 1-year survival rate in gastric cancer patients was 0.80(95%CI: 0.52-1.21, P = 0.29).The overall response rate of S-1 vs capecitabine was 0.94(95%CI: 0.59-1.51, P = 0.93).Compared with capecitabine regimens, the most frequent hematologic toxicities were neutropenia( O R = 0.9 9, 9 5 % C I : 0.6 5- 1.4 9, P = 0.9 4) a n d thrombocytopenia(OR = 0.72, 95%CI: 0.31-1.67, P = 0.44).The most frequent non-hematologic toxicities included nausea(OR = 0.85, 95%CI: 0.56-1.28, P = 0.43) and hand-foot syndrome(OR = 0.16, 95%CI: 0.10-0.27, P < 0.00001).CONCLUSION: The existing studies suggest that S-1 is not more effective than capecitabine in the treatment of gastric cancer patients, but does exhibit less toxicity with regard to hand-foot syndrome. AIM: To rationally evaluate the effect of S-1 vs capecitabine for the treatment of gastric cancer. METHODS: MEDLINE, EMBASE, Cochrane Controlled Trials Register, Google Scholar, and China Journal Full Text Database were accessed to collect clinical randomized controlled trials regarding the effect of S-1 vs capecitabine for the treatment of gastric cancer patients. Statistical analysis was performed by metaanalysis. Flow-controlled controlled trials of the inclusion criteria .RESULTS: Compared with capecitabine regimens, the 1-year survival rate in gastric cancer patients was 0.80 (95% CI: 0.52-1.21, P = 0.29) .Compacted with capecitabine regimens, the most frequent hematologic toxicities (OR = 0.72, 95% CI: 0.31-1.67, P = 0.44). The most frequent non-hematologic (OR = 0.9 9, 95% CI: 0.6 5- 1.4 9, P = 0.9 4) and thrombocytopenia toxicities included nausea (OR = 0.85, 95% CI: 0.56-1.28, P = 0.43) and hand-foot syndrome (OR = 0.16, 95% CI: 0.10-0.27, P <0.00001) .CONCLUSION: The existing studies suggest that S-1 is not more effective than capecitabine in the treatment of gastric cancer patients, but does exhibit less toxicity with regard to hand-foot syndrome.