A broadband light source device that can generate supercontinuum light in a visible range and having a spectrum with a stable shape and high intensity is provided. The broadband light source device includes a diode-pumped solid-state laser light source that outputs seed light in response to being excited by a laser beam output from a semiconductor laser light source; a wavelength converter that receives the seed light to generate wavelength-converted light having a wavelength different from that of the seed light, and outputs the wavelength-converted light; and a nonlinear medium that receives the wavelength-converted light to generate supercontinuum light having a bandwidth of 100 nm or greater included in a wave band of 400 nm to 700 nm inclusive, and outputs the supercontinuum light.