A laser light source device includes a pump light source which emits transverse-multimode light; a plurality of resonator mirrors which define a resonator, at least part of the resonator mirrors outputting light to the outside, where the output light having plural wavelengths; a laser medium arranged in the resonator, the laser medium being pumped with the transverse-multimode light emitted from the pump light source; and a wavelength conversion element arranged in the resonator, the wavelength conversion element being irradiated with a transverse-multimode line beam of fundamental wave obtained by oscillation at the laser medium and outputting a line beam of converted wave.