Infrared upconversion and optical storage thin film CaS∶Eu, Sm has been successfully developed by electron beam evaporation and radio frequency (rf) magnetron sputtering. Infrared upconversion efficiency of CaS∶Eu, Sm thin films with different thickness has been investigated by using the ultrashort infrared laser pulses with different FWHM. It is shown that upconversion efficiency of CaS∶Eu, Sm thin film not only depends on the growth conditions and the post annealing process, but also has the “exhaustion” phenomenon. By means of measuring transmittance and spatial resolution of CaS∶Eu, Sm thin film, the post annealing process was found to promote grain growth which could obviously improve upconversion efficiency of CaS∶Eu, Sm thin film, even though it had negative influence on transmittance and spatial resolution of CaS∶Eu, Sm thin film.