Abstract: Due to the uncertainty of the structural optimization in a complex mechanical system,in this paper an accurate identifying method for the boundary conditions based on sub-structure techniques is studied,a successive approximation topological optimization design is proposed to make the structural topology gradually achieve optimal structure. In addition,aiming at solving the problem of complexity to do CAE analysis for enterprise,an automatic system for automobile seat components based on the HyperWorks is constructed by using TCL language and other secondary development techniques. FEA analysis,simulation analysis and topology optimization design are realized. A component named the right side panel of an automobile seat skeleton is selected as a typical example to demonstrate the suggested design process and the detail functions of the developed automatic system. The result shows that the present methods are effective and the developed system has practical and efficient advantages during the CAE analysis process.