As sintering temperature increased, fracture behaviors of Al2O3/5 vol.% SiC nanocomposites were observed from transgranular type to mixture of transgranular and intergranular type. Specimen hot pressed at higher temperature showed the spalling on the fracture surface. Wear morphology of Al2O3/5 vol.% SiC nanocomposite displayed mainly microcracks and microchipping. Also, small amount of wear debris of Al2O3/5 vol.% SiC nanocomposite were observed because of strengthening of grain boundary due to the dispersion of SiC particles.