In this prospectively random study, the effect of oral Ftorafur as an adjuvant chemotherapy was compared with that of oral placebo in patients with Stage II and Stage III gastric cancer. Patients had undergone a subtotal gastrectomy with a resection margin that should have been free of tumors. Ftorafur (10 mg/kg) was given daily to 59 Group A patients. Multiple vitamins were given twice a week to 56 Group B patients. We found that there was no statistical significance in Stage II patients with regard to survival. In Stage III patients, those treated with oral Ftorafur had better 3-year and 5-year survival rates than those receiving oral placebo. This preliminary report on this ongoing study seems to indicate that long-term postoperative Ftorafur treatment may be beneficial to Stage III gastric cancer patients.