Abstract: The Neoproterozoic-Early Paleozoic metamorphic series in the western segment of the southern Altyn Tagh tectonic belt is lithologically composed of the middle-shallow metamorphic series containing three metamorphic zones of progressive metamorphism from greenschist facies to low-amphibolite facies，namely，sericite-muscovite zone，biotite zone and garnet-hornblende zone. The detailed study of metamorphic p-T path from garnet-hornblende zone indicates three metamorphic evolutionary stages: the middle-high pressure metamorphism(M₁) probably related to subduction and collision between ancient island arc and plate，at a depth of 30-35 km in response to crustal tectonic thickening at probable 7.27×10^{8-9.63×108Pa. Subsequent isothermal decompression process(M₂) took place at about 4.1×108-5.62×108 Pa as a result of rapid exhumation and the late retrograde metamorphic evolutionary stage(M₃) at decreased temperature and pressure. They make up a clockwise p-T evolutionary path and their geodynamic settings belong to those of plate collision and orogenic uplifting，indicating that the southern Altyn Tagh tectonic belt once experienced processes of subduction, collision and rapid uplifting.}

Key words: Neoproterozoic-Early Paleozoic metamorphic series, metamorphic p-T path, high-pressure metamorphism, western segment of the southern Altyn Tagh tectonic belt