Abstract: In the assembly design of combinational mobile machineries，various “functional components” and “building blocks”，being already constructed by CAD tools，are combined together to accomplish the required “functional combination” and “structural combination” of the intended product．The whole process of construction is illustrated in real time by 3DSMAX． This gives an effective way of reforming the traditional pattern of teaching machine design and graphics courses．It helps to improve the students’ ability of space thinking，space imagination and configuration design，thus develops a new way of providing machine design and graphics education．