Abstract: Three-dimensional solid model of movable arm of loader's working equipment was established by use of Pro/E, the finite element analysis and parametric design for the model were performed, and the movable arm was optimized after objective functions and constraint conditions were determined. The simulation result showed that forces and structural shapes of the movable arm are improved after being optimized on the premise of meeting requirment of the movable arm's work performance. The method of finite element analysis and optimization design based on Pro/E improves design speed and quality, reduces manufacturing costs, and has universal applicability to optimization research of movable arm of loader's working equipment and the whole working equipment.