A series of Zn:Ru:Fe:LiNbO3 crystals has been grown by Czochralski method. Their infrared transmittance spectra and UV-vis absorption spectra were measured and discussed to investigate their defect structure. The nonvolatile holographic recording of Zn:Ru:Fe:LiNbO3 crystals was characterized by the two-photon fixed method. We found that the recording time of Zn:Ru:Fe:LiNbO3 crystals became shorter and nonvolatile diffraction efficiency increases with the increase of Zn doping concentration, especially doping with Zn approaches the so-called threshold. And the nonvolatility is best when the concentration of ZnO up to 5 mol%. The intrinsic and extrinsic defects were discussed to explain the nonvolatile holographic properties in the crystals. (C) 2010 Elsevier B.V. All rights reserved.