Abstract: The vacuum-sintering technology were adopted to prepared micron particle Si₃N₄ matrixed nano-ceramics composite materials reinforced with nano-sized SiC particle.The mechanical performances of the composite materials are tested and the influences of nano-sized SiC on the mechanics performances and microstructure of Si₃N₄ ceramics were investigated.The results show that with the adding of nano-sized SiC particle,the mechanic performances of Si₃N₄/SiC(n) are enhanced and the microstructures are finer compared with the pure matrix Si₃N₄.