A light source apparatus includes: a light source; a light source driving section; a light detection section; a temperature detection section; and a control section being configured to, when determining that detected brightness is outside a range of brightness set for detecting abnormality in the light source or the light detection section and detected temperature is within a range of temperature set for detecting the abnormality in the light source or the light detection section, cause the light source driving section to perform driving of the light source for a case of abnormality in the light detection section, and when determining that the detected brightness is outside the range of brightness and the detected temperature is outside the range of temperature, cause the light source driving section to perform driving of the light source for a case of abnormality in the light source.