ZrC was produced by the combustion synthesis technology using Cu, Zr, and graphite as the starting element powders. The synthesis mechanism of ZrC was investigated by the combustion wave quenching experiment. Furthermore, the effects of sizes of C and Cu on the combustion synthesis behavior and products were also explored. Results revealed that ZrC was fabricated through the displacement reaction between C and Cu-Zr liquid. The Cu size hardly affected the combustion temperature and resultant products, indicating that the preparation cost of ZrC could be decreased by employing coarse Cu powders. With increasing C size, the burning temperature and ceramic particle size reduced. Graphite with size of 2.6 μm was used as the C source, and only ZrC nanoparticles and Cu were obtained. The products could be employed to prepare nano-sized ZrC/Cu composites without the elimination of by-products.