The effect of nickel on the conductivity of reaction*4]bonded SiC is studied. The results show that the resistivity of reaction bonded SiC decreases with increase of nickel content The Ni doped SiC has negative temperature coefficient of resistivity. The resistivity of SiC is almost constant with holding time at 900. The results above show that the resistivity of reaction bonded SiC can be improved through adding nickel. The microstructure of the Ni doped SiC is studied in detail.