Al 2 O 3 –30wt.%TiCN composites have been fabricated successfully by a two-stage gas pressure sintering schedule. The gas pressure sintered Al 2 O 3 –30wt.%TiCN composite achieved a relative density of 99.5%, a bending strength of 772MPa, a hardness of 19.6GPa, and a fracture toughness of 5.82MPam 1/2 . The fabrication procedure involves solid state sintering of two phases without solubility to prepare Al 2 O 3 –TiCN composite. Little grain growth occurred for TiCN during sintering while Al 2 O 3 grains grew about three times to an average size of 3–5μm. The interface microstress arising during cooling from the processing temperature because of the thermal and/or mechanical properties mismatch between the Al 2 O 3 and TiCN phase is about 50MPa. Such a compressive microstress is not high enough to cause grain boundary cracking that may weaken the composite but it can introduce dislocations within grains, which is very good to enhance the composite properties.