The straight silica nano-rods with a diameter of about 200nm and smooth surface were synthesized by chemical vapor deposition method at 1300°C. The as-synthesized samples were characterized by means of scanning electron microscopy, energy dispersive x-ray, and transmission electron microscopy. The results show that as-synthesized silica nano-rods have a uniform size, well-defined shape, and smooth surface. However, the morphologies and microstructures of silica nano-rods are affected by synthesis conditions, such as the concentration of the SiOx and the the deposition temperature. On the basis of these experimental results, a possible growth mechanism of silica nano-rods in this process is proposed.