The loader arm is a very important part of the working device of loader.The load is varied and its capability is key factor to the whole machine.So the optimization of loader arm is an import work to loader enterprise.The engineering analysis and optimization of loader arm could be finished by use Pro/E,which is a integration software of CAD/CAM/CAE.Firstly,the assembly model of loader arm is designed by the modeling module of Pro/E.Then,the engineering analysis and optimization of loader-arm were achieved by Pro/Mechanica integrated with Pro/E.