We present the case of a 58-year-old man who underwent distal gastrectomy for Stage III A advanced gastric cancer, identified as poorly-differentiated adenocarcinoma. He was diagnosed with recurrent peritoneal metastasis 11 months after surgery. S-1(80mg/m / 2)was administered as first-line chemotherapy, followed by weekly paclitaxel(80mg/m2)as secondline chemotherapy. Although a partial response was obtained, a peritoneal tumor in the upper abdomen, ascites, and an elevation in the serum carcinoembryonic antigen(CEA)level were observed. As the tumor proved resistant to paclitaxel, making the treatment ineffective, bi-weekly docetaxel(45mg/m2)was initiated. The tumor showed a partial response, the ascites disappeared, and the serum CEA level decreased. The time to progression was seven months until the appearance of ileus and ascites due to tumor re-growth. This paclitaxel-resistant gastric cancer with peritoneal recurrence proved responsive to docetaxel as third-line chemotherapy. Docetaxel may be active against gastric cancer that is resistant to paclitaxel because of the different effects of these two agents. Further clinical studies on the efficacy of docetaxel against paclitaxel-resistant gastric cancer are needed.