A 63-year-old man was found to have advanced gastric cancer and staging laparoscopy revealed positivity of peritoneal washing cytology. Since curative surgery was deemed not possible, we started chemotherapy using S-1 (80 mg/m2) orally administered for 2 weeks and paclitaxel (50 mg/m2) administered intravenously on days 1 and 8. After 3 courses of chemotherapy, the primary lesion and regional metastatic lymph node were diminished by CT. We confirmed a peritoneal washing cytology negative by laparoscopic examination. We performed a total gastrectomy and dissection of regional lymph node (D2). Pathologically, cancer cells disappeared both in the main tumor and lymph nodes, and histological efficacy was evaluated as grade 3. Adjuvant chemotherapy was done with same regimen, and he has had no recurrence as of 15 months after surgery.