This paper is a review for metasomatic processes in the mantle. The studies pertinent to mantle metasomatism began in the early 1970s. Since that time the contributions of the studies to our understanding of the nature and the mechanism of the mantle metasomatism involved in the evolution and heterogeneity of the mantle has been considerable.All of the studies show that mantle metasomatism may be very complex depending on the time, place, the type of agent and the nature of the fluid with various decoupled and cyclic events occurring at different depths of the mantle. Hence, future study pertinent to the generation, mechanism and conditions of the metasomatic processes in the mantle will undoubtedly prove to be as important for understanding depthly the evolution and heterogeneity of the mantle as those covered in this review. It may be very effective methods and ways for solving the generation, mechanism and time relationships between magmatism and metasomatism, to study depthly xenoliths from different place and type for metasomatism constraints, to combine traditional geology and petrology with modern test technique, and to combine subjects containing geology, petrology, geochemistry with geophysics.