To fully understand the friction and wear mechanism of chemical mechanical polishing process, the effects of different processing conditions on the polishing process were simulated. Three-dimensional CFD model considering multiphase flow and discrete phase was established to obtain the speed and pressure distribution of the polishing liquid as well as that of the polishing abrasive particles between wafer and polishing pad under different processing conditions. It is found that the abrasive particle distribution density is smaller when the film thickness is smaller, and the greater the speeds of the polishing pad and wafer, the smaller the particle distribution density. Based on the distribution characteristics of fluid velocity, pressure and polishing particles, a model of material removal rate(MRR) was established, and the dynamic pressure caused by flowing polishing abrasive on the surface asperity of the wafer during polishing process was analyzed. By applying the energy-balance fracture theory, the MRR prediction model was established which could be used quantitatively for all kinds of materials. For silicon carbide polishing, its MRR curve under different processing conditions was obtained by Matlab programing. It is found that the MRR is greater when the polishing pad speed is greater and the gap film thickness is smaller. The MRR decreases as polishing continues, and the effect of film thickness on the removal rate is smaller compared with that of the polishing speed.