Fixed diamond wire saw has the advantages such as higher cutting rate and clearer operating environment over the slurry wire saw in wafering. However, the higher cost and poor sliced wafer surface are still the obstacles for the diamond wire saw to totally replace slurry wire saw. In this study, the distribution of diamond grits on the wire was investigated by numerical simulation. The results show that there is a critical value of the abrasive interval to transfer the machining mechanism from plastic plowing to brittle indentation cracking for the material removal. The value depends on both the wire tension and bow angle during the operation.