A light source unit comprising: a light source; a color conversion material that converts incident light from the light source into light having a longer wavelength than the incident light; and a reflective film that exists between the light source and the color conversion material and that transmits light from the light source incident perpendicularly on the film surface, wherein the average transmittance is 70% or more in the light emission bandwidth of the light source in the transmission spectrum of the reflective film at an incident angle of 0° and reflects light from the color conversion material incident perpendicularly on the film surface, wherein the largest reflectance is 30% or more in the bandwidth of the light from the color conversion material in the reflection spectrum of the reflective film at an incident angle of 10°; wherein the P-Polarized light of the light incident from the light source on the reflective film surface at an angle of 20°, 40°, and 60° is reflected at a reflectance of R20(%), R40(%), and R60(%) respectively, which satisfy R20 < R40 < R60, characterized in that the reflective film is such that the short wavelength end of a reflection bandwidth of light incident at 60° on the film surface is on the lower wavelength side of the long wavelength end of the light emission bandwidth of the light source, and the short wavelength end of the reflection bandwidth of the reflective film is the lowest wavelength of the wavelengths corresponding to Rmax/2 (%) and is 400 nm or more, and the long wavelength end of the reflection bandwidth of the reflective film is the longest wavelength of the wavelengths corresponding to Rmax/2 (%) or more and is 1600 nm or less, wherein Rmax (%) is the largest reflectance in the wavelengths from 400 to 1600 nm in a reflection spectrum determined as described in the specification, and wherein the reflective film is a laminate film formed by alternately laminating 11 or more layers of different thermoplastic resins having a difference of 0.01 or more in refractive index in any direction from among any selected two directions perpendicular to each other in the plane of the reflective film and a direction perpendicular to the plane. a light source; a color conversion material that converts incident light from the light source into light having a longer wavelength than the incident light; and a reflective film that exists between the light source and the color conversion material and that transmits light from the light source incident perpendicularly on the film surface, wherein the average transmittance is 70% or more in the light emission bandwidth of the light source in the transmission spectrum of the reflective film at an incident angle of 0° and reflects light from the color conversion material incident perpendicularly on the film surface, wherein the largest reflectance is 30% or more in the bandwidth of the light from the color conversion material in the reflection spectrum of the reflective film at an incident angle of 10°; wherein the P-Polarized light of the light incident from the light source on the reflective film surface at an angle of 20°, 40°, and 60° is reflected at a reflectance of R20(%), R40(%), and R60(%) respectively, which satisfy R20 < R40 < R60, the reflective film is such that the short wavelength end of a reflection bandwidth of light incident at 60° on the film surface is on the lower wavelength side of the long wavelength end of the light emission bandwidth of the light source, and the short wavelength end of the reflection bandwidth of the reflective film is the lowest wavelength of the wavelengths corresponding to Rmax/2 (%) and is 400 nm or more, and the long wavelength end of the reflection bandwidth of the reflective film is the longest wavelength of the wavelengths corresponding to Rmax/2 (%) or more and is 1600 nm or less, wherein Rmax (%) is the largest reflectance in the wavelengths from 400 to 1600 nm in a reflection spectrum determined as described in the specification, and wherein the reflective film is a laminate film formed by alternately laminating 11 or more layers of different thermoplastic resins having a difference of 0.01 or more in refractive index in any direction from among any selected two directions perpendicular to each other in the plane of the reflective film and a direction perpendicular to the plane.