Hepatitis is a major public health problem all around the world. Hepatitis disease diagnosis via proper interpretation of the hepatitis data is an important classification problem. In this study, a comparative hepatitis disease diagnosis study was realized. For this purpose, a probabilistic neural network structure was used. The results of the study were compared with the results of the previous studies reported focusing on hepatitis disease diagnosis and using same UCI machine learning database. © Springer Science+Business Media, LLC 2010.