A light source apparatus includes: a plurality of solid-state light-emitting elements configured to emit lights having wavelength bands that are mutually different from one another a plurality of cooling units provided corresponding to the plurality of solid-state light-emitting elements and configured to cool the respective solid-state light-emitting elements a light-emitting element control portion configured to, when being given information related to an amount-of-light ratio of the plurality of solid-state light-emitting elements, perform light emission control of the solid-state light-emitting elements individually and a cooling control portion configured to control cooling capacities of the plurality of cooling units based on a cooling ratio corresponding to the amount-of-light ratio to perform cooling control of the respective solid-state light-emitting elements individually or in groups.