Compared with the traditional welding truss-column in shape of A,the members of the bolting top-joint are much smaller than the common welding joint.Furthermore,the members are more convenience on fabrication,transportation and installation.It should be noted that the zinc process is much easier and cheaper.In this paper,by using the finite element method,the effect of many factors to the global stiffness and the intensity of the bolting truss-column are analyzed;the factors include the column height,the root width to column height ratio,the tube thickness,etc.The results obtained are favorable references for design and optimization of the bolting truss-column of substation.