A microelement method for scale-span analysis of material microstructure and member macro re- sponse has been proposed. Instead of material parameter input for traditional mechanical analysis, the method is based on the input of metallographic diagram information. In order to express the material microstructure, this method arranges concentrated microelements in ordinary finite element before calculation, and transfers the node degrees of freedom of each microelement into the ones of the same finite element via compatibility conditions. This method can realize direct transition analysis from ma- terial microstructure to macro responses of members, while computation elements and degrees of freedom are equal to those of ordinary FEM. Based on the complicated microstructure diagrams pro- posed by material metallographic diagram, the mechanics responses of functionally graded plates are calculated and 3-D distributions of macro-mechanical variables and identical stress lines tendency on microstructure are given. A microelement method for scale-span analysis of material microstructure and member macro re- sponse has been proposed. Instead of material parameter input for traditional mechanical analysis, the method is based on the input of metallographic diagram information. In order to express the material microstructure , this method arranges concentrated microelements in ordinary finite element before calculation, and transfers the node degrees of freedom of each microelement into the ones the same finite element via compatibility conditions. This method can realize direct transition analysis from maize microstructure to macro responses of members, while computation elements and degrees of freedom are equal to those of ordinary FEM. Based on the complicated microstructure diagrams pro- posed by material metallographic diagram, the mechanics responses of functionally graded plates are calculated and 3-D distributions of macro-mechanical variables and identical stress lines tendency on mi crostructure are given.