Unilateral Choanal atresia is rare. Bilateral choanal atresia though common, is incompatible with life. 24-year female came with persistent complaints despite undergoing left-sided choanal atresia repair in childhood. Left-sided endoscopic assisted transeptal choanoplasty, posterior septectomy, and extended resection of rostrum of sphenoid done. Extended superior resection of rostrum of sphenoid increased success rate in our patient.