A three-dimension atomic-scale model with kinetic Monte Carlo method was used to simulate the evolution of microstructure, surface morphology and internal defects of {1 1 1}- and {1 0 0}-oriented planes of SiC film prepared by chemical vapor deposition, and the growth rate and growth velocity ratio of the two orientations were analyzed. Additionally, a two-dimension grain-scale model with Potts Monte Carlo method was used to simulate the process of competitive growth on the two orientations. The effect of different growth velocity ratio and nuclear density on SiC film morphology was discussed. Furthermore, the reason why the preferred orientations were {1 1 1} and {1 1 0} is analyzed by combining the above two scale models. It is proved that the morphology and preferred orientation of the film, simulated under actual experimental conditions, are consistent with those obtained by actual experiment. (C) 2008 Elsevier B.V. All rights reserved.