Abstract: On the basis of the theory of plate tectonics and by using the concept of tectonic facies andmethod of tectonic analysis,the West Tianshan Mountains and the northern margin of theTarim plate are divided into eight tectonic facies units,i.e. :the Kalpin, Kuqa and Kuruktagforeland thrust-bufacies,South Tianshan foreland molasse basin facies, Central Tianshan andSouth Tianshan magmatic arc facies and North Tianshan（fore-arc）and South Tianshan（back-arc） melange facies. This paper analyzes types of sedimentary facies and magmatic rocks ,pale-ontology,petrochemistry,isotopic ages and REE data of all tectonic facies areas in the Sinian toPermian andthen reconstructs the history of Paleozoic tectonic evolution of the West Tian-shan.