Abstract: The site type of a stand is the material basis for the growth of forest crop. In forestry practice establishing the site type of a stand exclusively by professional knowledge and practical experience may sometimes fall into fallacy, resulting in inadequate forest operations, hence economic loss.Based on the theory of Bayes and using factors closely related to site types of stands, the author developed a functional formula for site type identification. In practice, through tentative determination of the site type of a stand by experience supported by calculation with the identification formula, it is possible to secure a very precise assessment of the site type, thus providing a theoretical basis for adopting desirable silvicultural measures.