Endoscopic sinus surgery is a common surgical method to treat chronic sinusitis, nasal septum deviation, nasal polyps, turbinate hypertrophy and other common nasal diseases. Endoscopic surgery is usually performed under general anesthesia. Endoscopes with different angles such as 0 degree, 70 degree and 30 degree were used during the operation, and the nasal mucosa, sinus opening and nasal cavity neoplasia were observed under the guidance of endoscope. Under the guidance of nasal endoscope, the focus can be found accurately, the focus can be removed, the ostium of sinus can be opened, the drainage of sinus can be improved, and the anatomical abnormalities in the nose can be corrected, such as deviated nasal septum and inverted middle turbinate.