Abstract: Two kinds of cermets (cermet A and B) and their cutters (Tool A and B),were sintered by TiC micronpowders with TiN nanoparticles and TiC0.7N0.3solution nanopowders under pressureless condition.The study of microstructures and cutting tests showed that ceramic phases of A had black cores surrounded by grey rims,while B exhibited black and white cores with grey rims.TiN nanoparticles distributed among ceramic grainboundaries can improve strength of ceramic matrix.Tool A behaved higher cutting performances in comparison with Tool B at the same cutting conditions.Oxidation and diffusion wears accelerated failing progress of cermet cutters at higher cutting speeds.