Abstract: Objective To analyze the distribution and CT imaging characteristics of fungus ball sinusitis. Methods Seventy-eight patients diagnosed as fungus ball sinusitis by pathology after endoscopic surgery were admitted to Chinese PLA General Hospital from October 2014 to January 2015, and their medical data was retrospectively analyzed with lesion distribution and CT imaging features. Results Fungus ball sinusitis affected unilaterally in 66 cases (84.62%) and bilaterally in 12 cases (15.38%), of which, maxillary sinus was most frequently affected (64, 82.05%). CT findings showed soft tissue density within the sinus with punctate, linear, or cloud-like calcifications in 58 cases (74.43%); The bony walls of the sinus were sclerotic and thickened in 59 cases (75.64%). Conclusion Fungal ball sinusitis commonly affected only a single sinus with the predilection for the maxillary sinus. It is characterized by soft tissue density within the sinus with foci of calcific deposit and sclerosis and thickening of the wall of the paranasal sinuses in CT imaging. De finitive diagnosis still relies on pathological examination.