ZnO nanorods were synthesized from high purity Zn granule by a vapor phase deposition in the Ar + O2 gas. The products were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The ZnO nanorods were typically 1~2 μm in length and 20~30 nm in diameter with an aspect ratio as high as 20. The UV absorption properties were detected and the results show that the ZnO nanorods have an extremely strong absorption at 200~380 nm wavelength. The results were good when the ZnO nanorods were used as photocatalyst.