 This study is an open-label, single-center, and randomized phase II study designed to evaluate each efficacy and safety of S-1 and capecitabine in the elderly andor poor performance status patients with recurrent or metastatic gastric cancer. The randomization will be stratified by age 70-85 years versus 65 years and 70 years and performance status, which is dependent on age group; in 70-85 years, ECOG performance status 0-1 versus 2 and in 365 years and 70 years, ECOG performance status 2 versus 3. 