In this study, when physician make a diagnosis of Sasang constitution of patients, anthropometric data are applied to seek the classification function into Sasang constitution. Data used in the analysis are the anthropometric data of 550 patients who had been treated in nine oriental medical hospital, and our data have no missing value in 12 anthropometric variables. In order to improve the accuracy of classification function into Sasang constitution, we consider one method of variable transformation of anthropometric data based on oriental medicine.