The UV photorefractivity of $\mathrm{Li}\mathrm{Nb}{\mathrm{O}}_3:\mathrm{Hf}$ was investigated by beam distortion and two-wave coupling experiments. A sharp decrease of beam distortion was found between Hf concentrations of 2 and $2.5\mathrm{mol.}\mathrm{\%}$ , indicating a significant increase of photoconductivity there. The energy-transfer direction of the two-wave coupling and the effect of chemical reduction on the UV photorefractivity reveal that electrons are the carriers responsible for the UV photorefraction. Moreover, dissimilar with $\mathrm{Li}\mathrm{Nb}{\mathrm{O}}_3$ highly doped with Mg, Zn, and In, the grating recorded in $\mathrm{Li}\mathrm{Nb}{\mathrm{O}}_3:\mathrm{Hf}$ was found to be nearly stable in the dark but sensitive to red light, which can be attributed to the special location of Fe ions in the crystal lattice.