A 53-year-old man had consulted another physician regarding his epigastralgia and anorexia. Since gastric cancer was detected, he was referred to our department. An upper gastrointestinal endoscopy revealed a type-2 gastric cancer at the upper portion of the lesser curvature of the stomach, and an abdominal CT scan showed marked swelling of periaortic lymph nodes. Since a radical resection appeared impossible, we used preoperative chemotherapy with a combination of TS-1 and CDDP. The patient was administered TS-1 for 3 weeks at 120 mg/ day, received an intravenous drip infusion of 90 mg/body of CDDP on day 8, and then discontinued chemotherapy for 2 weeks, which was regarded as one course. After 2 courses of the chemotherapy, an upper gastrointestinal endoscopy showed that the primary tumor was reduced in size, the periphery of the tumor almost flattened, and an abdominal CT scan confirmed the loss of swelling in the periaortic lymph nodes. The responsive rate was evaluated as PR. Since a radical resection was considered possible, we performed a total gastrectomy with complete D3 extirpation combined with a splenectomy. Histological efficacy was evaluated as grade 2 in primary cancer, and grade 3 in lymph nodes. Regrettably, the patient died one year and 7 months postoperatively. However, we consider the TS-1 and CDDP in combination useful as preoperative chemotherapy for advanced gastric cancer with periaortic lymph node involvement.