Temperature effect on the self-deflection of Guassian beam in photofractive crystal is investigated by taking into account the temperature dependence of both diffusion effect and dark irradiation. Taking the Gaussian beam as the solitary beam,numerically solving the beam propagation equation in which the diffusion term has been taken into account,it is found that the center of the Guassian beam moves along a parabolic trajectory and,moreover the bending distance of the Guassian beam center increases first,reaches its maximum value at a specific. temperature,and after that decreases as temperature contionuously rises when the crystal temperature changes in a regime,whereas it will unstable or break down if the temperature change is large enough. The self-deflection of Gaussian beam in photovoltaic photorefractive crystal can be reshaped by appropriately adjusting the crystal temperature.