The Fuping Group in Pingshan County, Hebei Province, is a suite of high-grade amphibolite-facies rocks. From its micro-features, the rocks underwent anatexis in some areas. The effect of the anatexis is most promi- nent in sillimanite-K- feldspar leucogranulitite (leptite) of the Xiaojue area. The electron microscopic observation shows that the sillmanite-K- feldspar leucogranulitite studied has been modified in the process of anatexis. There appear many distinct micro-area mineralogical characteristics which are mainly different degrees of corrosion of pre-existing minerals such as K-feldspar (Kf1), perthite, quartz (Q1), albite (Ab1), biotite (Bi1) and magnetite (Mt1) , remobilization and reconstitution of the main component elements and formation of recrystal-lized minerals, e, g. sillimanite, quartz, mica, feldspar and rutile along the cleavages and fissures of the minerals and in their interstices. There are two possible mechanisms of element remobilization in the process of anatexis: (1) selective removal from the lattices of the pre-existing minerals, and (2) melting of pre-existing minerals. Fe and Ti removed from biotite formed the recrystallized magnetite (Mt2) and rutile, while Si and Al removed from the biotite and feldspar formed sillimanite (Sill) and quartz (Q2).