The crystalline basement of the Kon Tum Massif, Central ViÖt Nam, consists mainly of from amphibolite to granulite facies metamorphic rocks of the Kan Nack and Ngäc Linh Groups and associated magmatic complexes. The petrographical study on the granulites has been showing that mineral associations of garnet-orthopyroxene-sillimanite-quartz gneiss (UHT pelitic granulite) and garnet-clinopyroxene-orthopyroxene-quartz gneiss (UHT mafic granulite) are stable in ultrahigh-temperature conditions, while those of garnet-cordierite-sillimanite-biotite± spinel gneiss (normal granulite) are stable in lower temperature conditions. The peak metamorphic conditions of T = 1000-1050° C and P = 1,1-1,2 GPa are estimated for the UHT granulites, and T = 700-850° C and P = 650 MPa - for the normal granulites. Various reaction textures indicate the multi-phase symplectite formation during their metamorphic evolution. Clockwise P-T paths have been determined for both UHT and normal granulites during 250-260 Ma isothermal decompression.