The porous TiC ceramic was prepared by reaction sintering method, using TiO2, carbon black as reactants, TiC as additives. The effects of the addition content of TiC on grain size, pore size, open porosity and bending strength were investigated. The results indicate that with an increase of TiC in range from 0% to 100%, the particle size of TiC formed by reaction increases from 0.17 μm to 0.71 μm; the pore size enhances from 0.15 μm to 1.51 μm; the open porosity decreases from 78% to 38%. Additionally the bending strength increases first and then decreases, when addition content is 80%, achieves the highest value of 86 MPa. The growth mechanism of TiC is due to the addition of TiC causing a decrease in the carbon content around TiO2, which leads to a decline in the melting point, an enhancement in diffusion capacity, and an increase in grain size of TiC formed by reaction.