Cubic silicon carbide (3C-SiC) nanowires were synthesized through a reduction-carburization route by using silicon powders and tetrachloride (CCl4) as Si and C sources, and metallic Na as the reductant at 700 degrees C. The as-prepared SiC nanowires were characterized and studied by X-ray powder diffraction, transmission electron microscopy, X-ray photoelectron spectra, Raman backscattering, and photoluminescence spectra at room temperature. The SiC nanowires produced from the present route typically have diameters of 15-20 nm and lengths of 5-10 mu m. The influencing factors of the formation of the SiC nanowires were discussed and a possible growth mechanism for the SiC nanowires was proposed.