Objective To discuss the application of optical image guided system in the endoscopic sinus surgery . Methods Under the guidance of optical image guided system , endoscopic sinus operations were performed in 32 complex cases from October 2012 to June 2016.All of the 32 patients underwent preoperative routine examination and sinus CT scan before surgery , and 3 of the patients underwent additional sinus MRI scan .The CT and MRI data were inputted navigation system for 3D reconstruction.During the operation, head marker registration and facial contour registration were done after general anesthesia to make sure the distance between actual position of surgical instruments and navigation image position ≤1 mm.When endoscopic surgery was performed , a positioning navigation surgical instrument was placed at a target and positioned on a navigation display when a structure was required to be positioned. Results The average preoperative preparation time for image-guided surgery was 14 -37 min ( mean,24.4 min). Obvious deviations (>1 mm) during navigation were found in 5 cases (15.6%) and were corrected in time .Local congestion of the forehead skin appeared in 3 cases and return to normal on the next day .All of the 32 cases were successfully operated without intraoperative or postoperative complications .Critical structures were successfully recognized and located (100%) during operations , such as skull base , orbital papyracea , arteriae ethmoidalis anterior , canales opticus , and drainage openings of frontal and sphenoid sinus.In 7 tumor cases, 4 orbital invasion cases, 15 chronic sinusitis cases,2 sinus osteoma cases, and 3 sphenoid sinus cyst cases, lesions were removed radically .In the cerebrospinal rhinorrhea case , the rhinorrhea was successfully repaired with the help of image guided system.During postoperative follow-ups for 6 -12 months, there was no recurrence in these cases . Conclusion Image guided system can improve the safety , accuracy and thoroughness of complex cases of endoscopic sinus surgery , especially in the sinus anatomic variation cases , re-operation cases , and cases with extensive sinonasal mass or with orbital /skull base invasion .