Abstract: To solve the problem of hoisting large-scale slender columns with unequal sections , an optimal scheme to carry out the whole erection is studied and the corresponding software is developed. Mathematical models for the internal forces corresponding to different hoisting schemes are established. The positions of hoist points are selected as design variables for the optimal model. The objective of the analysis is to minimize the maximum internal forces (bending moment) in the process of erecting. The constraints are imposed by penalty strategy. With grid method and genetic algorithm, the optimal problem is solved. By comparing the different induced moments due to different hoist point positions, one set of optimal positions of hoist point is determined. A practical example is presented to demonstrate the correctness of the analysis and explain the need of optimizing hoist points of slender columns with unequal sections.