Abstract: The paper develops a new method to calculate the potential field of the asteroids with arbitrary mass distribution. The accuracy of this method is based on both the resolution of the polyhedron and the truncation error of the Legendre series. Here we compare the potential fields get by both our method and the traditional method using homogeneous polyhedral model to indicate the feasibility of our method. We also show the differences in the potential fields and the corresponding equilibrium points between the homogeneous model and the heterogeneous model to emphasize the great importance of the heterogeneous model in the researches about the dynamical environment of asteroids.