Numerical method has been used to analyze the opto-thermionic refrigeration proc ess of semiconductor heterostructure. Based on the drift-diffusion model, curren t continuity equation and Poisson equation are employed to calculate the distrib ution of carriers, the radiative recombination rate and the Auger recombination rate of the semiconductor. In addition, we have calculated the effect of the cha nging of barrier height and the doping density on the refrigeration rate. Thus t he optimum conditions of opto-thermionic refrigeration have been obtained based on these results. This work is of great significance for guiding the experiment research in the future.