Abstract: Cutting performances of ultra-fine TiC0. 7N0. 3cermet cutting tools were investigated and compared with those of ordinary cermet and carbide cutting tools. The exponential formulas of the cutting forces were obtained based on the experimental data. The lives of the ultra-fine TiC0. 7N0. 3 cermet cutting tools under study are 2. 5 and 3 times as long as those of ordinary cermet and carbide cutting tools, the cutting forces decrease by 9% to 10%, and the machined roughness is as low as 0. 7μm, obviously lower than those of ordinary cermet cutting tools (1. 3μm) and carbide cutting tools (1. 2μm).