The present paper is a cross-sectional microradiographic study. Postmortem hemimandibles were radiographed with a microfocal high-resolution method. Microradiographic appearances of the feline periodontium are described and discussed. Mean relative alveolar bone support in clinically and histologically normal cats was 46.9%. Site-specific alveolar bone support (ABS) was calculated twice (blind). The 95% confidence limits of the method error for one observation were estimated. Differences between two site-specific measurements did not exceed +/- 2.72%. Microfocal radiography yielded valuable additional information about the feline periodontium and made it possible clearly to identify important dental and periodontal structures such as the CEJ (cementoenamel junction) and the bottom of infrabony defects.