Abstract: The traditional method used for analyzing the multipactor of the dielectric is particle-in-cell method, but it has some shortcomings, such as time-consuming, large amount of computation and so on. The numerical simulation of multipactor in the dielectric surface breakdown in strong oblique DC field is realized by using statistical methods. The V-T graphs of the number of secondary electrons, average transit time and other key parameters are given. The influence of the smooth surface coefficient and the secondary electron yield coefficient of dielectric on the multipactor are investigated. The results show that the multipactor exists in the tilt angle area under strong oblique DC field, the multipactor may not occur while the tilt angle is too large or too small. If the tilt angle is located in susceptible area, the number of electrons in saturation will gain inversely with the inclination angle. Choosing the dielectric material with lower secondary electron yield coefficient, we can get a better inhibiting performance of multipactor.