Objectives: was to determine the role of cone beam CT (CBCT) in diagnosis of otosclerosis. Study Selection: This was a prospective study. 40 patients (18 males and 22 females) were recruited from the audiovestibular medicine unit in Al-Azhar university Hospital, Assiut in the period between 1-12-2020 to 1-7-2021 Their age ranged from 20 years to 50 years with the mean age 34.8 +_ 9.7 years. Data Synthesis: Data were collected, coded, revised and entered to the Statistical Package for Social Science (IBM SPSS) version 20. Findings: As regard degree of hearing loss in all studied patients. At right side, it was mild in 4 patients (10%) and moderate in 36 patients (90%). At left side, it was normal in 2 patients (5%), slight in 2 patients (5%), mild in 26 patients (65%) and moderate in 10 patients (25%). There were 27 patients (67.5%) with thickened stapes footplate at right side and 25 patients (62.5%) with thickened stapes footplate at left side. As regard thickened stapes footplate side, it bilateral in 25 patients (992.6%) and unilateral in 2 patients (7.5%) Conclusion: CBCT is a new imaging technique with a considerably lower radiation dose than conventional MSCT. This study shows the potential of high-resolution CBCT imaging of more conclusive results on the potential of CBCT as a diagnostic tool of the middle ear, assessed as having better image quality and a lower radiation dose than MSCT.