YVO 4: Bi 3+, Eu 3+ nanophosphor converts near ultraviolet light to red light and shows lower scattering loss for visible light and long-term photostability. Therefore, the authors produce urethane resin films containing YVO 4: Bi 3+, Eu 3+ nanophosphors on soda-lime glass substrates as spectral shifters to understand the effects of doping of Bi 3+ and Eu 3+ into YVO 4 and the Bi 3+ concentration on photoelectric conversion efficiencies of a monocrystalline silicon photovoltaic module. Under ultraviolet and near infrared light radiation, the YVO 4: Bi 3+, Eu 3+ films enhance the photoelectric conversion efficiency of the module through spectral down-shifting as compared to the bare glass substrate and the YVO 4 film. In contrast, the YVO 4: Bi 3+, Eu 3+ films are not effective for improving the photoelectric conversion efficiency under the simulated solar light radiation. These results are discussed from the aspects of the optical transparency and the photoluminescence properties.