A 63-year-old man who had suffered from anorexia and body weight loss was admitted to the hospital. Upper GI series and an endoscopic examination revealed type 3 cancer in the posterior wall of the cardia. Abdominal CT scan showed enlargement of No. 16 lymph nodes. Preoperative diagnosis was stage IV gastric cancer (T3 (SE) H0 P0 N3), and we considered a curative operation impossible. Therefore, neoadjuvant chemotherapy with TS-1 and low-dose cisplatin (CDDP) was planned. After 4 weeks of administration, the primary lesion was reduced in size and the No. 16 lymph nodes were shrunken remarkably. Therefore, a total gastrectomy with a splenectomy, a distal pancreatectomy, and D3 lymph node dissection was performed. Histological findings demonstrated the degeneration of cancer cells and fibrosis in the primary tumor and metastatic regional lymph nodes. There were no viable cancer cells in the No. 16 lymph nodes. The histological changes against neoadjuvant chemotherapy were judged to be Grade 1b for the main tumor and Grade 3 for the No. 16 lymph nodes. Neoadjuvant chemotherapy with TS-1 and low-dose cisplatin is so effective in a short period that can be adapted to advanced gastric cancer for downstaging.