The finite element analysis model of the cutting force of the impact resistant diamond saw blade was established. The numerical simulation and comparative study of the cutting force of the diamond circular saw blade were carried out on the two kinds of tooth structures, with the conventional U-shaped sink and the new semi-circular sinktooth shape. The simulation results show that under the same load, the deformation and stress of the saw blades with new semi-circular sinktooth shape are significantly improved compared with that of the traditional U-shaped sink. The deformation of the saw blade is reduced by 11.56%, the first and third principal stresses are reduced by 24.04% and 34.19% respectively. Therefore, it has good performance of bearing large load and impact resistance.