In the last decade, a great deal of attention has been focused on functional endoscopic sinus surgery(FESS) for the treatment of chronic paranasal sinusitis. The keys to FESS are an understanding of the underlying mechanism of paranasal sinus diseases and the ability to diagnose the causes accurately. The purpose of FESS is to reestablish ventilation and mucociliary clearance of the sinuses. The goal is achieved by the endoscopic removal of disease from key areas of the anterior ethmoid and middle meatus(ostiomeatal complex). Therefore this method can provide successful and safe surgery with experienced hands and complementary CT of paranasal sinus for chronic paranasal sinusitis which almost rhinogenic origin, spreading from the nose into the sinuses. So authors introduce the new method and procedure of FESS in our experiences.