Objective To investigate a new surgical approach for presacral lesion by double door via S3- 5. Methods From June 2007 to January 2008, 5 female patients (56-84 years old) with presacral lesion were treated. One patient had straining feel ing in anus, 2 patients had difficult defecation and bloody stool and 2 patients had no symptoms. Digital rectal examination revealed rectal tumor in 2 cases and anus examination of presacral tumor showed no abnormal ity in 3 cases. B-ultrasound, CT and MRI examination displayed presacral tumor in 3 cases and rectumal tumor in 2 cases. The size ofthe lesions was 4 cm × 3 cm × 3 cm - 20 cm × 15 cm × 13 cm. The disease course was 12-50 days (average 18 days). All 5 patients received total resection of tumor through the surgical approach featured by double door via S3-5. Results The operations were successful in all the 5 patients, and no severe presacral venous hemorrhage, rectal injury, direct injury of pelvic nerve and structure damage of pelvic bottom occured during operation. The approach exposure time was 12-28 minutes (average 20 minutes) and the blood loss for approach was 30-130 mL (average 80 mL); and the operation time was 80-120 minutes (average 105 minutes) and the blood loss during operation was 100-350 mL (average 280 mL). All incision healed by first intention. Pathological examination of resected tissue after operation revealed presacral teratoma in 1 case, dermoid cyst in 1 case, spindle cell tumor in 1 case and rectal tubiform villus adenoma in 2 cases. All the patients suffered from perineal hypoesthesia to various degrees after operation, which were recovered to the normal 6 months later, and X-ray films showed bone union occurred in all the cases. No gatism occured. During the followed-up period of 6-13 months, no sacrum defect, pelvic instabil ity and sacroil iitis was observed in the 5 cases. B-ultrasound, CT and MRI examination showed no recurrence of tumor. Conclusion The approach of double door via S3-5 is a simple and safe surgical procedure featured by a good surgical exposure with less bleeding, short operative time, no sacrum defect, no severe sacral nerve damage, and early postoperative convalescence.