A 51-year-old man with unresectable adenosquamous cell carcinoma classified Borrmann type 3 of the stomach was treated with combination chemotherapy. The treatment consisted of two parts: intraabdominal administration of CBDCA (400 mg/body) during the operation, and transcatheteral intraabdominal infusion of CDDP(100 mg/m2) on day 1 and oral administration of UFT (400 mg/m2) on day 1 to 28 from a month after the operation. The latter therapy was performed every four weeks, and was administered two times. Primary gastric region was improved like a type II-C endoscopically, and metastatic lymphnode measuring 5 cm diameter disappeared on a computed tomography after the treatment. Thus, total gastrectomy was performed. No cancer cells were shown in both the resected stomach and dissected lymphnodes upon histological examination. Generally, patients with unresectable gastric cancer have a poor prognosis. But we concluded that the survival time and the quality of life in this patient were remarkably improved by the effective combination chemotherapy.