A light-source device includes: two long-wavelength light sources that emit red long-wavelength light beams (LWLs)； a broadband light source that emits a green broadband light beam (BL)； and a multiplexing portion that multiplexes a wavelength region greater than a first predetermined wavelength λ1 of one of the LWLs having a longer peak wavelength and a wavelength region equal to or less than λ1 of the other LWL having a shorter peak wavelength, and that multiplexes a wavelength region greater than a second predetermined wavelength λ2 of the other LWL and a wavelength region equal to or less than λ2 of the BL, wherein intensities of the LWLs at λ1 are equal to or greater than 10% of the peak intensities thereof and intensities of the other LWL and the BL at λ2 are equal to or greater than 10% of the peak intensities thereof.
