Abstract: In order to solve the problem of insufficient stiffness of neutral column in lightweight design of heavy CNC machine tool, the three-dimensional model of heavy CNC machine tool column is reconstructed by Pro/E; then the model is imported into finite element analysis software to carry out the statics, dynamics and topology optimization analysis, and the overall structure of the column is analyzed and reconstructed. The influence of the spindle box balance system on the column is fully considered, and the boundary conditions are treated and simplified. According to the analysis results, it shows that the stiffness of the reconstructed column structure is improved and the quality is reduced, which meets the design requirements.