Abstract： Objective The value of coronal high-resolution CT was assessed in the evaluation of paranasal sinus diseases. Methods A retrospective study of paranasal sinus CT imaging of 100 patients,which were confirmed by surgery and pathology. Bachlying、 coronal scanning, 3 mm slice thickness, 6 mm slice pitch and high-resolution bone algorithm reconstruction for all the patients. We got there groups according to the CT manifest: anatomy variation、inflammation and tumor Results There were 55 patients and 118 sites in anatomy variation group, all the images can display the important structure of anatomy variation and ostiomeatal complex clearly ;70 patients in inflammation group and 10 patients in tumor group,which were all confirmed by surgery and pathology. Conclusion HRCT could accurately diagnose paranasal sinus diseases,and completely describe the lesion of either the sinus wall and out of the sinus. HRCT should be the routine examination before FESS, it has great clinical value for designing surgical plan and evaluating the effect and recurrence.