CASE 1: A 72-year-old man with epigastralgia was diagnosed with gastric cancer and referred to our hospital. An abdominal CT scan revealed liver metastasis and para-aortic lymph node metastasis. He was treated with S-1+CDDP. After 4 courses of this treatment, the liver metastasis and para-aortic lymph node metastasis disappeared, and adjuvant surgery was performed. There has been no recurrence for 16 months postoperatively. CASE 2: A 66-year-old man with anorexia was diagnosed with gastric cancer and referred to our hospital. An abdominal CT scan revealed para-aortic lymph node metastasis. He was treated with S-1+CDDP. After 9 courses of this treatment, para-aortic lymph node metastasis disappeared, and adjuvant surgery was performed. Eight months after the operation, lymph node metastases were confirmed by abdominal CT scan, and he was treated with chemotherapy as an outpatient as of 13 months after the operation. We experienced two cases of Stage IV gastric cancer undergoing adjuvant surgery after down staging by chemotherapy. It was suggested that adjuvant surgery to highly advanced gastric cancer could improve the prognosis of patients.