Based on the principle of gear meshing, the tooth profile equation of the meshing side of the pin rail wheel and the pin row is derived by using the coordinate transformation equation. The solid model of the pin rail wheel is established on the basis of the tooth profile equation, the bending stress of the root of the gear is calculated by the finite element software ANSYS, and the stress sensitive part of the tooth profile of the pin rail wheel was found. Applying the optimization design function of ANSYS, the objective function of two groups of different design variables is optimized in order to minimize the bending stress of tooth root of pin rail wheel, and the optimal tooth profile and tooth profile parameters of pin rail are obtained, respectively. The obtained conclusions can provide theoretical basis for further system research of pin rail wheel, and has a certain practical significance.