Abstract: Taking SiC powder and TiC powder as raw materials, Al₂O₃-Y₂O₃ as sintering aid, SiC-TiC ceramic composites were prepared by pressureless liquid phase sintering, and the effect of TiC content (35vol%-45vol%) on the microstructure and properties of the ceramic composites was studied. The results show that the phase composition of the ceramic composites was SiC, TiC, YAG(Y₃Al₅O₁₂)and YAM(Y₄Al₂O₉). With increasing TiC content, TiC particles were formed to be a continuous network structure gradually; the open porosity of the ceramic composites decreased first and then increased, the relative density, flexural strength, fracture toughness, Vickers hardness and volume resistivity increased first and then decreased, and the volume resistivity decreased. When the TiC content was 40vol%, the ceramic composites had the excellent comprehensive properties, and the relative density, open porosity, flexural strength, fracture toughness, Vickers hardness and volume resistivity were 98.1%, 0.28%, 429 MPa, 5.87 MPa·m^1/2, 26 GPa and 1.66×10^-5 Ω·m, respectively.