A light source apparatus includes: a control section that acquires information relating to a ratio of a light amount value for light with second wavelength band to a light amount value for light with first wavelength band, obtains a light amount value for the light with the first wavelength band so that an observation image has a predetermined brightness, and, from the information relating to the ratio, determines a light amount value for the light with the second wavelength band, and generates light adjustment information for making first and second semiconductor light sources emit light with the light amount value for the light with the first wavelength band and the light amount value for the light with the second wavelength band and a drive section that, based on the light adjustment information generated by the control section, drives the first and second semiconductor light sources.
