Abstract: The TAS diagram, which is widely used in academia, is a classification scheme for volcanic rocks approved by IUGS in 1989. This classification has been active in advancing the research on petrology and geochemistry, regulating the naming of rocks (especially volcanic rocks) and facilitating the exchange of academia. However, it cannot be denied that earlier studies had some limitations due to analytical methods, analytical techniques and data volume limitations. Now that the world has accumulated a huge amount of data, researchers should have the conditions for making new discussion on the classification of volcanic rocks. In this study, the authors have developed a new TAS classification scheme for volcanic rocks using a probability density function. The original TAS diagram defines 15 root names, among which 9 are preserved in this paper. With the addition of one new root name, the authors define a total of 10 root names. The biggest change in the new TAS diagram is in the alkaline rock series. In the new TAS diagram, the trachybasalt series is closed up, thus making up for the earlier TAS classification in the acidic rock part of the deficiency. The authors have also found that the TAS diagram may have some problems. The classification scheme presented in this study is subject to further discussions and tests.