The microstructure and mechanical properties of a new-type of cermets cutter (tool A) with nano-TiN modification and its cutting properties in cutting gray cast iron are investigated. SEM and TEM observations of the microstructure of the above material reveal that nano-TiN modified cermets possess a finer microstructure than conventional cermets. In the cutting tests, for comparison, cemented carbide cutter (YG8, tool B) was also utilized. The cutting results show that the cutting properties of tool A are superior to those of tool B. It is also found that the predominant failure mode of tool A is normal wear and micro-spalling under lower cutting quantities, and that chipping occurs under higher cutting quantities. SEM analysis reveals that cohesion, oxidation and diffusion wear become very apparent at a higher cutting speed. On the contrary, grain wear also exists but is not apparent. The microstructure and mechanical properties of a new-type of cermets cutter (tool A) with nano-TiN modification and its cutting properties in cutting gray cast iron are investigated. SEM and TEM observations of the microstructure of the above material reveal that nano-TiN In the cutting tests, for comparison, cemented carbide cutter (YG8, tool B) was also utilized. The cutting results show that the cutting properties of tool A are superior to those of tool B. It is also also found that the predominant failure mode of tool A is normal wear and micro-spalling under lower cutting quantities, and that that takes up higher than the cutting quantities. SEM analysis reveals that cohesion, oxidation and diffusion wear become very apparent at a higher cutting speed. On the contrary, grain wear also exists but is not apparent.