Many reports have advocated the feasibility of using an endoscope for the treatment of cerebrospinal fluid (CSF) rhinorrhea and skull base defect, and diversified endoscopic techniques and repairing materials have recently been proposed. This study determined the effectiveness of endoscopic repair of CSF leaks and interpreted the indications of the lumbar drain. Retrospective follow-up. A total of 39 patients with CSF rhinorrhea (20 traumatic, 13 iatrogenic, and 6 spontaneous) were treated in one institution over a 10-year period. An underlay procedure was used to make eight (20.5%) repairs by way of a turbinate composite graft (4 patients), turbinate mucosa graft (3 patients), or the Dura Substitute (Preclude) (1 patient). A free turbinate graft with the applied fibrin glue was used to repair the defect by way of an overlay procedure in 23 (59.0%) lesions. Abdominal fat was used to repair the other eight (20.5%) lesions. Defects in the cribriform plate and anterior ethmoid sinus comprised the majority (61.5%) of all lesions. The successful rates for overlay, underlay, and fat obliteration procedures were 91.3% (21/23), 87.5% (7/8), and 100% (8/8), respectively. There were no statistical difference between underlay and overlay techniques (P = .792, Student's t test). Lumbar drainage was performed in 18 of 39 (46.2%) cases. Most patients required nasal packing (89.7%) and prophylactic parenteral antibiotics (97.4%). CSF rhinorrhea was resolved during the first attempt in 36 of 39 (92.3%) patients. All leaks were successfully repaired after a second attempt. No major complications were encountered. The endoscopic approach is safe and effective for the treatment of CSF rhinorrhea, even in the cases not successfully treated by previous neurosurgical approaches. Lumbar drain was suggested for defects in the frontal and sphenoid sinus and defects associated with meningocele or encephalocele. Complete exposure of the defect, appropriate selection of a fitting graft, as well as accurate placement and stabilization of the graft are critical to the success of repair.