An 80-year-old woman was diagnosed with advanced gastric cancer of T2N0H0P0M0, Stage IB. She was strongly advised to undergo surgery, but refused this option. Because the performance status (PS)was 1, combination chemotherapy with S1 100 mg/day (day 1-21) and CDDP 50 mg/m2 (day 8) was initiated. After one course of treatment was completed, she changed her mind and expressed the wish to undergo an operation for her disease, which led to proximal gastrectomy (double tract reconstruction) being performed. A histopathological examination revealed CR of the disease with no cancer cells. As the population grows older, the number of elderly patients with advanced gastric cancer will increase in the future. Therefore, S-1 and CDDP combination therapy may be a treatment of choice for gastric cancer with dose reduction according to patient status, if the elderly patient refuses a curative operation. It may well prove to be an effective treatment in the elderly provided the dosage and administration are appropriate.