The two-dimensional image makes it difficult to determine the anatomic locations during the Functional Endoscopic Sinus Surgery (FESS), which causes many complications. The nasal columella is the best mark to identify the distance to the operating sites during the FESS. In this study, we measured the distances and angles from the base of columella to each important landmark: the anterior end of the middle turbinate, the ethmoid bulla, the posterior and superior end of the uncinate process, the basal lamina, the posterior wall of the ethmoid sinus, the posterior and superior wall of the sphenoid sinus, the anterior and posterior ethmoid artery and the ostia of the frontal sinus and the maxillary sinus in 12 Chinese adult cadavers (24 sides). Then a simple method was proposed to identify where you are operating on and where is the most perilous point. We also paid attention to the thickness of bony wall of the optic nerve canal, the superior wall of the sphenoid sinus, the papyraceous lamina and the septa of the ethmoid air cells and found that the former two were much thicker than the latters. The thicker bony wall may contribute enough safety to the optic nerve and the hypophysis in FESS.