A 54-year-old male had huge pre-sacral recurrent mass (54 × 41 mm) at the level of S1 sacral bone six months after he underwent a high anterior resection for advanced rectal cancer. He was considered inoperable although he had no distant metastasis. We planned a surgical resection for the recurrent tumor after the chemo-radiation therapy (radiation + CPT-11, UFT, Leucovorin). The tumor had a good response (33 × 29 mm) for CRT allowing a dissection area between sacral bone and posterior tumor margin. The surgical resection was performed. We dissected recurrent tumor and sacral bone below S2 and preserved S1 nerve roots under direct vision in order to prevent complications such as walking disorder and spinal fluid leakage. The operative time was 870 minutes and the blood loss was 3,600 g. There were no intraoperative complications. Macroscopically, surgical margin was well secured and a pathological examination of resected specimen revealed microfoci of cancer cells. The post operative hospital stay was 36 days. The patient is alive without any evidence of recurrence 72 months after surgery. He has no walking disability, and a good quality of life.