In this work we studied photorefractive effect of lithium niobate sLiNbO3d doped with Zn, In, and Na atultraviolet sUVd wavelength down to 351 nm. It is found that the UV photorefraction of LiNbO3 doped withZn, In, or Na was enhanced significantly as compared to that of the nominally pure LiNbO3. Our results showthat the statement that the property of resistance against photorefraction in highly Zn and In doped LiNbO3 iscorrect only in visible light range. By contrary, these crystals exhibit as excellent photorefractive characteristicsin UV. We also find that there are doping concentration threshold values of Zn and In for the disappearance ofthe light-induced lens-like effect both in visible and in UV, but such concentration threshold values are notfound for UV photorefraction within the highest doping concentrations we used. In highly Zn or In dopedLiNbO3 crystals, diffusion dominates over photovoltaic effect and electrons are determined to be the dominantcharge carriers in UV photorefraction. The results are of interest to the study on the defect structure of LiNbO3.Further investigation on this field is greatly urgent.