Titanium carbide based cermets with additions of titanium nitride nanoparticles were fabricated by using ultrasonic dispersion and conventional powder metallurgy techniques. In order to characterise the microstructure, SEM and TEM have been utilised. The results show that the microstructure becomes ® ner with increasing additions of titanium nitride nanoparticles. The mechanical properties were also measured and the results show that the properties do not change monotonously with the amount of titanium nitride nanoparticle addition. Good properties can be obtained when the amount of TiN addition reaches 6 ± 8 wt-%. The improvement of properties is mainly owing to the re® nement of TiC grains as well as the de¯ection effect of titanium nitride nanoparticles on crack propagation.