A brief historical review on the genesis of granitoid has been given and a preliminary genetic classification has been proposed on the basis of the genesis of Jiangxi granitoids. According to this classification, the granitoid has three groups,(1) crustal type granites formed by remelting of the sial; (2) transitional type granites foamed by mixed-melting of the upper mantle or the sima with the lower crust; and (3) mantle type granites derived from differentiation or contamination of basaltic magmas. Each type is further subdivided into several sub-types.