Abstract:Abstract:The helium isotopic composition of each sphere of the Earth has its characteristic isotopic ratios. These ratios show significant differences. Therefore, helium isotopes, as a tracer, are more sensitive than other isotopes to distinguishing crust from mantle materials. Up till now, geochemical behaviors of helium isotopes during the HP-UHP metamorphism have not been well studied, it led to the limited application of helium isotope in eclogites. Many HP-UHP eclogite belts have been discovered in China. These eclogites can be genetically classified into two types: one is associated with subduction of the continental slab, and the other is formed by the subduction of the oceanic slab. This paper reviewed the progresses therefore of HP-UHP eclogite facies metamorphic rocks well studied and some problems and future work of the application of helium isotope in eclogites are also discussed.