Disclosed is a backlight device for illuminating a transmissive color liquid crystal display panel from its backside with white light. The backlight device includes, as a light source, a plural number of principal light emitting diode units 21mn, and a plural number of subsidiary light emitting diode units 21mn, where m and n are natural numbers. Each principal light emitting diode unit is made up by a plural number of light emitting diodes (21) arrayed in a string and emits white light of preset chromaticity. Each subsidiary light emitting diode unit is made up by a plural number of light emitting diodes (21) arrayed in a string and emits white light of chromaticity in the vicinity of the preset chromaticity. The number of the subsidiary light emitting diode units is smaller than that of the principal light emitting diode units. When the principal light emitting diode units and the subsidiary light emitting diode units are arrayed in a two-dimensional matrix, the subsidiary light emitting diode units 21mn are arrayed without being juxtaposed on the same row, and the subsidiary light emitting diode units 21mn, arrayed in a center column of the two-dimensional matrix, are arrayed towards the center of a color liquid crystal display panel (110).