Abstract: Giant accretionary complexes form at active margins by scraping off oceanic sediments from the subducting plate. Whether or not those compositionally complicated accretionary complexes would be ultimately transformed into mature continent crust remains an unsolved question that calls for further investigation. The Chinese Altai section of the Central Asian Orogenic Belt (CAOB), the largest accretionary orogenic belt on the earth, preserves complicated tectono−thermal geological records and is characterized by formation of mature continental crust, making it a natural laboratory for studying the reworking of accretionary complexes and their evolution into mature continental crust. This paper focuses on the main orogenic period (Silurian−Devonian) of the Chinese Altai and systematically summarizes its recent research progresses in terms of metamorphism−deformation, anatexis, and granitization. ① The Ordovician accretionary complex underwent multiple−stage deformation involving compression−extension−compression during the Silurian−Devonian period, accompanied by intense metamorphism and widespread anatexis during the extensional deformation stage; ② The Ordovician accretionary complexes and most Silurian−Devonian granites in the region exhibited significant similarities in their geochemical characteristics. More importantly, the chemical compositions of Silurian−Devonian granites resemble those of the modelled partial melts of the accretionary complex under regional anatexis P−T conditions. ③ Regional deformation processes facilitated crustal differentiation and the formation of mature continental crust. Together with regional available data, this contribution proposes that the intense crustal reworking during the Silurian−Devonian of the Chinese Altai Orogenic Belt was related to changes in the dynamics of the related supra−subduction system. The cyclic switching between subduction advance and retreat in accretionary orogenic belts could lead to changes of regional stress field and provide anomalous heat source for crustal anatexis, thus control the processes of crustal anatexis and mass redistribution. In these regards, anatexis of accretionary complexes, plays a pivotal role on transformation of active continental margin sediments into compositionally differentiated mature continental crust. This may be a key mechanism contributing to the peripheral continental growth in accretionary orogenic belts in general.