The present invention relates to ZnO green luminescent material and its preparation. The ZnO green luminescent material is prepared by doping a trivalent rare earth ion compound and a Li compound into zinc oxide material. The method comprises the following steps: (1) weighing raw material in the stoichiometric ratio of formula ZnO: xA, yLi, (2) grinding the raw material, sintering it at 800-1200° C. for 2-8 h, cooling to the room temperature, and then obtaining the ZnO green luminescent material. The present ZnO green luminescent material doped with trivalent rare earth ion compound and Li compound has high stability and luminous intensity, and has higher low-voltage cathode ray luminescence efficiency. The method can easily be operated and can be used widely.