Disclosed is a backlight device which is used for a color liquid crystal display and includes a light source and a backlight housing (23). The light source includes a red light emitting diode (21R), radiating red light, having a peak wavelength λpr such that 625 nm≦λpr≦685 nm, a green light emitting diode (21G), radiating green light, having a peak wavelength λpg such that 505 nm≦λpg≦540 nm, and a blue light emitting diode (21B), radiating blue light, having a peak wavelength λpb such that 420 nm≦λpb≦465 nm. The backlight housing mixes the red light, the green light and the blue light, radiated from the light source, to generate white light. A light emission intensity is adjusted so that a half value width of a spectrum of the red light, a half value width of a spectrum of the green light and a half value width of a spectrum of the blue light are such that 20 nm≦hwr≦25 nm, 30 nm≦hwg≦40 nm and 25 nm≦hwb≦30 nm, respectively.