The zinc oxide nanopowders were prepared by direct precipitation method and homogeneous precipitation method,respectively.The as-prepared samples by these two methods were characterized by X-ray diffraction(XRD),ultraviolet visible absorption spectroscopy(UV-Vis),infrared spectroscopy,and other physical means.The crystal structures and antibacterial properties of the samples were also compared and investigated.Results showed that the sample prepared by homogeneous precipitation method had smaller particle s...