A 46-year-old woman with lower abdominal distension was diagnosed as gastric cancer in our hospital. She had multiple metastases of lungs, lymph nodes, bilateral ovaries, and uterus. After she underwent sub-total gastrectomy, bilateral oophorectomy, and total hysterectomy, she received adjuvant chemotherapy followed by docetaxel and S-1. After 6 courses of chemotherapy, PET/CT revealed no recurrences (complete response), and she was therefore administered S-1 for only 6 months. She has remained without recurrence 15 months after the operation.