We report a case of advanced gastric cancer with pyloric stenosis, in which a curative resection was performed following gastrojejunostomy and S-1 based chemotherapy. A 46-year-old female presenting with vomiting was diagnosed with unresectable gastric cancer with pyloric stenosis after a detailed examination. She underwent laparotomy, which revealed a T4 tumor invading the pancreas head and involving the gallbladder. A gastrojejunostomy was performed. After the operation, chemotherapy of S-1(100mg/body, days 1-21)plus cisplatin(85mg/body, day 8)was administered. After 4 courses, the tumor size was markedly reduced upon imaging examinations. Six months after gastrojejunostomy, distal gastrectomy was curatively performed. The pathological findings were type 3, por1, pT4a(SE), pN1, M0, pStage III A. After 5 courses of S-1(100mg/day, days 1-28)as adjuvant chemotherapy, she had a recurrence at a lymph node behind the pancreas head. Despite irinotecan+cisplatin following docetaxel therapy, she had no effective benefits and died from the cancer 17 months after the first operation. The prognosis of unresectable gastric cancer with pyloric stenosis is not promising; however, gastrojejunostomy following S-1-based chemotherapy could lead such patients to curative resection and a longer survival time.