Abstract: The turbomolecular pump is widely used to obtain clean-high vacuum. In this paper, the experimental particle Monte Carlo algorithm is used to calculate the two-dimensional model using COMSOL, and the single-stage blade row pumping performance parameter database is updated, and on this basis, a new method for calculating the transmission probability of the turbine blade row area weighting is proposed. At the same time, the calculation program is written according to the improved algorithm. The area weighting method is closer to the working conditions of the turbine blade row. Using this method improves the calculation accuracy, provides reliable support for the calculation of the turbomolecular pump combined blade row, and provides a method and basis for the design and performance evaluation of the turbomolecular pump.