A 56-year-old woman with advanced gastric cancer with peritoneal metastasis was successfully treated with multidisciplinary therapy. Gastrectomy and total resection of the peritoneal metastasis were performed initially. Subsequently, combined chemotherapy with S-1/polysaccharide-Kureha( PSK) and intraperitoneal infusion( IP) of docetaxel( TXT) was continued for 9 months. Because of the appearance of hepatic metastasis, the anti -cancer drug was changed to irinotecan (CPT-11) that was administered by dropping intravenously( DIV therapy) and continued for 10 months. Despite the reduction of the hepatic metastasis, ascites was increased. All metastatic lesions disappeared after 3-months of paclitaxel (TXL) DIV therapy. Five years after the operation, the peritoneal metastasis recurred. Combined DIV and IP TXL therapy was administered for 2 months. The peritoneal metastasis was reduced and the TXL DIV therapy was continued for 6 months. Due to increased levels of tumor markers, capecitabine( Xeloda)/cisplatin( CDDP) was introduced; however, it could not be continued because of the side effects. Subsequent TXT DIV therapy was not effective; chemotherapy was switched to CPT-11 DIV therapy, which was effective for 14 months. S-1 and TXL IP therapy was initiated because of the appearance of a new peritoneal tumor. This therapy effectively controlled the disease until today. The patient is in good health at 8 years after the start of therapy.