Gastric endocrine cell carcinoma is known to be highly malignant with a poor prognosis, and no standard treatment has been established. We experienced a case of endocrine cell carcinoma of the stomach with liver and lymph node metastases. The lesions became resectable at curability B after chemotherapy with S-1/cisplatin (CDDP). A 59-year-old man, who had no specific complaint, had gastrointestinal endoscopy for screening. A 30-mm tumor was found at the greater curvature of the lower body of the stomach, and was histologically diagnosed as an endocrine cell carcinoma from the biopsy specimen. A computed tomography (CT) scan and abdominal magnetic resonance imaging (MRI) showed masses at S5 and S6 of the liver, and No. 4 lymph node enlargement. Diagnosed as gastric endocrine cell carcinoma with liver and lymph node metastases, he was referred to our hospital. We started chemotherapy with a daily dose of S-1 administered on days 1 to 14 and CDDP of 70 mg/m(2) on day 8, every 4 weeks. After three courses of treatment, the primary lesion became a small scar and the metastatic lesions vanished from the CT and MRI. Then we performed distal gastrectomy with lymph node dissection and partial liver resectomy. Histological findings revealed no cancer cells, except for a few cells in the S5 liver lesion.