Abstract: Altgn Tagh structure zone has been studied by many geologist for the significance of geodynamic and its peculiar location-structure transformation in the north margin of Qing-hai-Tibet plateau.The Altgn Tagh rock group is the Altgn Tagh structure zone's crystalline basement.And studying of it was on a few geological routes in the past survies.Based on regional geology mapping of 1:250000 scale,the author analyzed systematically the rock constitution and deformation of structure of the preliminary Altgn Tagh,and found out that the preliminary Altgn Tagh rock group is made up of neutral-acidic the old metamorphic intrusive body,superacrustals and eclogite and garnetiher zolite-bearing high-ultra high pressuremet amorphic rocks from out side in different periods of Pre-Cam brian,called the Altgn Tagh complexes.The real Altgn Tagh rock group is only metamorphic superacrustals.The deformation and all kinds of block and rocks and their relationship are complex.The Altgn Tagh complexes,which had undergone Pre-Cambrian the formation of crystalline basementre-building in main orogenic period of early Palaeozoic-defo rmations within mainland in late Palaezoic,is alarge complex structure zone.