A numerical method is used to evaluate the surface photovoltage (SPV) in semiconductors as a function of surface recombination velocity, photon flux, substrate doping level, and oxide charge. It is found that SPV is reduced by the surface recombination. For a certain surface recombination velocity SPV increases approximately as the logarithm of photon flux. The effect of surface recombination on SPV is dependent on substrate doping level and oxide charge, to sum up, on the energy-band bend. SPV for depletion surface is more remarkably affected by surface recombination than that for strong inversion surface.