Abstract: Turbomolecular pump is widely used in the semiconductor and thin film industry,nuclear physics,and surface science.It is the core mechanical equipment to obtain an ultra-high vacuum environment.Based on the machinability of the integrally formed turbine rotor,this paper proposes a structural improvement scheme for the turbine blade and uses the two-dimensional model and the three-dimensional model to evaluate the performance of the improved structure:under the same geometric structure,the ho coefficient of the two-dimensional model is slightly higher than that of the three-dimensional model,and the compression ratio is slightly lower than that of the three-dimensional model.The improved model not only solves the machinability of the turbine blade root,but also improves its maximum ho coefficient and maximum compression ratio to a certain extent.