To provide a light source device generating light of an arbitrary color or illuminance on a chromaticity diagram prescribed by CIE or the like by use of a plurality of light emission sources of primary colors, and keeping a color or illuminance after color mixture constant even if a change of a spectral emission luminance of a light emission element by a change of a drive electric amount is present.

This light source device mixing light of three primary colors to output the prescribed light has: a storage means storing information showing relation between emission light intensity and the drive electric amounts of the light emission elements emitting the light of three primary colors; and a control means calculating the drive electric amount of each the light emission element corresponding to a value of chromaticity, an illuminance or a luminance of the prescribed light on the basis of the relation of the emission light intensity and the drive electric amounts.