To provide an observation system and a light source control apparatus capable of more efficiently generating observation light to be used for special observation different from normal observation, and enabling the special observation to be more efficiently performed.An observation system includes: a plurality of light sources that emits light of different wavelength bands that can be combined to generate white light; an optical system that irradiates an observation object with first light that includes light emitted from some of the plurality of light sources; an imaging device that captures an image of the observation object irradiated with the first light; and a light source control unit that controls the quantity of the first light on the basis of the luminance of a pixel corresponding to a predetermined wavelength band in the captured image.