A light source system includes a luminescent wheel, a driving unit for rotating the luminescent wheel, a light source for shining excitation light on to a luminescent material layer of the luminescent wheel, a light shining control unit for controlling an illumination timing of the light source, a light shining time integrating unit for integrating individual excitation light shining times to a plurality of predetermined divided areas of the luminescent wheel, an integrated light shining time storage unit for storing the individual light shining times to the predetermined divided areas, and a light shining range control unit for equalizing times over which excitation light is shone on to the plurality of predetermined divided areas of the luminescent wheel based on the individual excitation light shining times to the predetermined divided areas.