A light source device includes: a rotating body configured to be rotated with a rotating shaft as a center; a first wavelength conversion portion arranged on a circumference of a circle of a predetermined radius with the rotating shaft as the center in the rotating body, and configured to be irradiated with light to generate light of a wavelength different from a wavelength of the light; and a second wavelength conversion portion arranged on a circumference of a circle of a radius larger than the predetermined radius with the rotating shaft as the center in the rotating body, configured to be irradiated with light to generate light of a wavelength different from a wavelength of the light, and including a characteristic that conversion efficiency of the wavelength declines due to rise of a temperature more than the first wavelength conversion portion.