The metamorphic grade of granulites must reach to the granulite facies but not all the rocks of granulite facies are exclusively granulite. The granu- litc` always contains some hypersthene and>10% of plagioclase and posse- sses the granoblastic texture and granulitic structure. Based on their mine- ral modal composition a further classification of the granulites is made in a triangular compositional diagram, with feldspar(plagioclase士orthoclase士quartz) -anhydrous ferromagnesian minerals (Hypezsthene+diopside1garnet, etc)一 hydrous ferromagnesian minerals(hornblende士biotite) as its three vertices. The 0-30, 30-60 and 60-100 percent of plagioclase(1orthoclase1quartz) contents are taken as the ranges of the melanocratic, mesocratic and leucogranulite， respectively. The mineral modal composition of monomineral rocks ranges from 90% to 100%.The distingction of granulites from plagioclase-amphibolite and gneises has set up and 14 granulites and related rocks have been subdivided.