The electrical resistivity of MoSi2-SiC composites containing different SiC contents were measured and formulated by topological method. The theoretical result and the experimental value were in good agreement with each other. It is indicated that the electrical resistivity of the bulk composites can be increased by increasing volume fractions of the higher electrical resistivity of SiC phase and reducing the MoSi2 phase. The best fitting function may predict the SiC volume fractions and microstructures of the electrical resistivity composites, and give a guideline for material design. (C) 2004 Published by Elsevier B.V.