By comparing the 2 types of the segment erector structure,the general lifting mechanism and the parallelogram mechanism,it is found that the parallelogram mechanism is superior to the general lifting mechanism in the spatial arrangement and structural performance.With the modeling analysis of the parallelogram lifting mechanism,the parallelogram lifting mechanism is optimized designed by use of MATLAB optimization toolbox.By comparing the force curves of the hydraulic cylinder before and after optimization,the result shows that the optimized force of hydrocylinder is smaller than that before optimization.