A laser beam source device includes: a light source which emits light having fundamental wavelength; a wavelength conversion element which converts the light having fundamental wavelength into light having conversion wavelength; a resonance element which transmits first light converted into the conversion wavelength light and reflects light not converted; an optical path conversion element which releases second light contained in the light reflected by the resonance element and converted into the conversion wavelength light in the same direction as the direction of the first light, and releases the light not converted toward the light source; and a supporting member. The resonance element is disposed in such a position that one end surface of the resonance element on the second light side is shifted to the supporting member from one end surface of the wavelength conversion element on the second light side.