목적: To assess the efficacy of multilayered reconstruction technique using the vascularized pedicled nasoseptal flap for high-flow cerebrospinal fluid (CSF) leak after endonasal endoscopic skull base surgery(EENS). 방법:We retrospectively reviewed 47 patients who underwent EENS with high flow CSF leak and reconstruction by multilayered technique including nasoseptal flap from January 2013 to January 2015. Pituitary adenoma was not included in this study because they were usually treated well without multilayered reconstruction. 결과:In this population, we encountered six postoperative CSF leaks (12.8%). It is notable that five CSF leaks (25%) occurred in our first 20 repairs, whereas we encounted only 1 leak (3.7%) in the last 27 patients. All of our failures All six failed repairs were due to our technical problems, and necessitated a revision procedure. All revisions were successfully done with the previously used nasoseptal flap. 결론:Multilayered reconstruction using nasoseptal flap is excellent option for decreasing CSF leaks after EENS with high flow CSF leaks. However some technical details and learning curve is necessary.