In published series on presacral tumors, 5% to 15% of tumors are neurogenic origin. We report a rare and giant intrapelvic schwannoma which may be the biggest tumor ever reported with literature review. A 52-year-old male presented with lower back pain and voiding difficulty for about 3 years ago. Magnetic resonance image (MRI) revealed huge neurogenic tumor (15.5×9.5×11.0 cm) originated from sacral plexus, especially S2. The patient underwent low anterior abdominal approach by general surgeon. When abdominal cavity was exposed, thinned bladder wall was not differentiated from peritoneum. Primary repair was needed because of injury of bladder wall. Demarcation of tumor was well preserved and tumor was easily separated from the capsule. Subtotal resection of tumor was done. Presacral tumors, irrespective of origin, cause similar symptoms due to their location in the presacral space. The mode of presentation reflects the tumor size, mass effect and presence of infection. These may manifest locally as back pain, rectal pain or neurological defects. Prior to any surgical intervention, information of tumor is important: tumor size, extent of loco-regional dissemination, involvement of the tissue planes between neighboring structures, and the degree of vascular involvement. In operation, adhesion may present surrounding pelvic structure then surgery had to subtotal removal of tumor rather than total removal. In these cases, piecemeal resection of tumor is recommended. We thought that huge size tumor surgery was carefully performed because of important pelvic organ injury that make severe neurologic deficit.