Calculations of the differential photon-production cross sections from proton-nucleus collisions in the energy range 15 to 150 MeV have been carried out and compared with experimental measurements on 12C, 16O, 27Al, and 56Fe. The calculations are based on the intranuclear-cascade-evaporation model of nuclear reactions and simple assumptions about the deexcitation of excited nuclei. The calculated total photon-production cross sections are within roughly a factor of two of the experimental values, but the calculated photon spectra are not in good agreement with the experimental spectra.