The present invention provides a luminance-enhancing film including a λ/4 plate, and a reflection polarizer, including a first light reflection layer, a second light reflection layer, and a third light reflection layer from the λ/4 plate side sequentially, the light reflection layers being light reflection layers formed by fixing a cholesteric liquid crystalline phase, and including blue, green and red light reflection layers, and Rth(550) of the first light reflection layer and Rth(550) of the second light reflection layer having inverse signs; and a luminance-enhancing film including a λ/4 plate and a reflection polarizer including at least a light reflection layer formed of a rod-like cholesteric liquid crystal material and a light reflection layer formed of a disk-like cholesteric liquid crystal material. The luminance-enhancing film has high luminance and is able to suppress an oblique change in the color.