Dedicated high-resolution small animal systems have recently emerged as important new tools for animal research. One of these imaging systems is computed tomography that permits veterinarians to non-invasively screen animal for diagnostic purposes and to monitor disease development and response to therapy. Before any tools can become an effective diagnostic modality, normal specific data of the species have to be characterized. Having access to clinically applicable computed tomographic anatomy of the cat is the basis of effective utilization of this modality in veterinary medicine. The aim of this study was to determine the anatomic structures of computed tomographic images of the cat brain. Five mature mixed breed cats with average weight of 3-3.5 kg were used in this study. After physical examination, one of animals was fixed by routine anatomical method and the others were anaesthetized and restrained in special frames. Then the brain of each animal was scanned transversely and dorsally. The thickness of each slice considered 3 mm. Thereafter, the cats were euthanized and sectioned with cuts as closely as possible to the C.T. slices. C.T. images were compared with the fixed (first) cat and anatomical slices. Intact, sagitally and dorsally sectioned cat skulls were used as reference models. Finally relevant structures and landmarks were identified and labeled in C.T. images. The result of this study can be considered as reference data for diagnosis of abnormal conditions and evaluation of treatment procedures of the brain.