Al 2 O 3 -TiN-TiC ceramic materials with different Ni content were fabricated by hot-pressing technique. Mechanical properties such as flexural strength, Vickers hardness and fracture toughness were obtained by three-point-bending test and Vickers indentation method. The microstructures of the sintered body were observed by scanning electron microscopy. The effects of Ni content on the microstructures and the mechanical properties of Al 2 O 3 -TiN-TiC ceramic materials were investigated. The results indicated that the addition of Ni could change the topography of the microstructures which displayed various core-shell structures. Moreover, the fracture mode changed with the increment of Ni content. When the addition of Ni was 3 vol%, the flexural strength and fracture toughness were the greatest and the improvement could be explained by the unique microstructures of sintered bodies.