Abstract: The authors briefly introduce new results obtained recently in the study on the tectonicsof the South Tianshan Mountains. （1）Late Silurian MOnograptus sp. has been discovered. （2）The Precambrian Ku’ergan tectonic window has been identified according to the 606 Ma RbSr isochron age of the biotite-tremolite-quartz schist. （3）Late Paleozoic ophiolites have beenconfirmed to exist in the South Tianshan Mountains according to the age of fossil radiolariansin chens of ophiolitic melanges and the single-mineral 40Ar/39Ar high-temperature plateauage of 333. 51±8. 77 Ma of plagioclae from gabbros.