The importance of computed tomography (CT) in analyzing temporal bone diseases has increased, and the ability to reconstruct the temporal bone structures in three dimensions from multiple CT films has been required. In order to facilitate the visualization of temporal bone structures, we tried reconstructing temporal bone CT images three-dimensionally using a personal computer, and evaluated the possibility of using three-dimensional CT images clinically. Temporal bone CT scan films from five cases of cholesteatoma and a case of otosclerosis as control were examined. Four temporal bone structures (temporal bone contour, middle ear, mastoid, and inner ear) and cholesteatoma, extracted from enlarged black and white CT films, were inputted to the personal computer. Data import and image reconstruction procedures were performed using commercially available software. Our results indicate that three-dimensional reconstructions contribute to visualizing temporal bone structures spatially, and to choosing surgical approaches in difficult cases, such as petrous bone cholesteatoma. In conclusion, three-dimensional reconstructions using a personal computer is useful in the diagnosis and treatment of cholesteatoma.