The ion implantation and annealing at high temperature in oxygen atmosphere was used to prepare LiNbO3 samples with different Zn2+ implantation concentrations. The effects of different Zn2+ implantation concentrations and annealing state on the ultraviolet and infrared properties of LiNbO3 crystal were studied. In ultraviolet wave band,experiment results show that Zn2+ implantation makes LiNbO3 absorption band edge shift to longer wavelength,and annealed samples have the same absorption band edge with pure LiNbO3 crystal. Zn2+ implantation reduces transmittance of LiNbO3 crystal. In infrared wave band,the pure LiNbO3 crystal appears the primary and secondary peaks in 3486cm-1,2851cm-1,2917cm-1,respectively. And compared with pure LiNbO3 crystal,the positions of the primary absorption peaks for Zn implantation samples occur slightly red shift. The secondary absorption peaks for X-cut LiNbO3 crystal are obvious. The secondary absorption peaks for Z-cut LiNbO3 crystal are not obvious before annealing,but become sharp after high temperature annealing. Zn2+ implantation enhances the transmittance of X-cut LiNbO3 crystal,but reduces the transmittance of Z-cut LiNbO3 crystal.