High resolution CT is well known excellent modality for evaluation of fine eqr structures and its changes, but is not usual method for detection of inflammatory disease of ear. Forty cases of OMPC were reviewed and advantages & limitations were also evaluated. RESULTS : 1. On CT findings of OMPC, abnormalities were external auditory canal in 14 cases, tympanic membrane in 31 cases, soft tissue mass in middle ear cavity and/or mastoid antrum in 34 cases, middle ear effusion in 9 cases, and bony labyrinth in 5 cases. 2. Partial erosion and missing of ossicles were long process and lenticular process of incus, body of incus, head of malleus, and stapes in order. 3. Advantage of temporal bone CT were early detection of soft tissue mass, evaluation of extent of disease, destruction of bony structure and ossicular destructioin. 4. Differentiation of cholesteatoma and granulation was difficult and examination of superstructures such as stapes and facial nerve canal were limited.