The Ce3+ doped CsPbBr3 nanocrystals were prepared by hot-injection method, the crystal phase structure, micro-morphology, chemical composition, light absorption performance, luminescence performance, fluorescence lifetime and optical efficiency of luminescent solar concentrators (LSC) devices were characterized by XRD, TEM, XPS, UV-Vis, PL, Time-resolved fluorescence spectroscopy and J-V curve test. The experimental results show that the cubic phase Ce3+-doped CsPbBr3 nanocrystals with good dispersion and average grain size of 12.26 nm are successfully prepared by hot-injection method. The optical band gap and fluorescence emission peak intensity of Ce3+ doped CsPbBr3 nanocrystals shows a trend of increasing and then decreasing with the increase of Ce/Pb molar ratio. When n(Ce)/n(Pb)=0.25, the optical band gap reaches a maximum of 2.416 eV, the luminescence intensity is the strongest, and the fluorescence emission peak blue-shifts from 515 nm to 510 nm for pure CsPbBr3 nanocrystals. The luminescence performance and stability of Ce3+ doped CsPbBr3 nanocrystals are enhanced. The optical efficiency ηopt of Ce3+ doped CsPbBr3 nanocrystals with polystyrene solution for the preparation of composite thin-film LSC is up to 6.81%.