A 61-year-old man with esophagus invasive advanced gastric cancer and peritoneum dissemination underwent three courses of S-1/CDDP/Lentinan (LNT) combination neoadjuvant chemotherapies (T3N1P1H0, Stage IV) (It is S-1 80 mg/m2,CDDP 15 mg/m2 and LNT 2 mg/body twice/week for two weeks) since down staging was obtained. We performed the surgery of total gastrectomy, splenectomy, D2 lymph node dissection, and Roux-en Y reconstruction in March 2008. With the surgical examination, there was no ascites and peritoneal dissemination. Although there was serious infiltration, we were able to remove it. In the histopathological effect judgment, it was Grade 1b. We changed the therapy to S-1 alone after the same chemotherapy for six months. One year after the operation, he is still alive one year after the surgery.