The present invention provides a method preparing zinc peroxide and zinc oxide using solar energy. The zinc acetate and hydrogen peroxide are chosen as raw material. The zinc acetate is dissolved in amixed solution of hydrogen peroxide and deionized water. A white sol is obtained by reaction under sunlight illumination. The white sol is dried and a buff powder which is zinc peroxide powder is obtained. Then the powder is annealed in high temperature and a white zinc oxide powder is obtained. Through controlling pH value of the sol and reaction time, nanometer grain of zinc peroxide and zinc oxide which are provided with grain-controlled, good dispersivity, high purity and high crystallinity are obtained. Preparation method of the present invention is simple in process, easy in operating,mild in reaction condition and can be completed at room temperature, which has the advantages of energy-saving and environmental friendly.