Abstract: Nano-tetrapod zinc oxide whiskers were prepared by vapor-phase oxidation under high temperature,with molecular sieve as the catalyst. X-ray diffraction analysis（XRD） shows that all the products are pure ZnO with wurtzite structure. Reaction temperature and system pressure are proved to have great effects on the morphology of T-ZnO_W. When prepared under constant pressure,the morphology of the whiskers changes with the increasing of reaction temperature. Nano T-ZnO_W with perfect structure can be obtained when the system pressure and reaction temperature are 11083Pa and 1038℃ respectively. While under constant temperature, the dimension of the products reduces with the reducing of the pressure. Uniform nano T-ZnO_W with root dimension of 20nm to 80nm and length of 500nm to 2μm can be obtained when the pressure is lower than 11083Pa. TEM results show that the arm of the nano T-ZnO_W is single crystal and the nucleus is twin-crystal. The growth process of the whisker is accorded with the vapor-solid mechanism.