A semiconductor laser light source emits a laser beam for pumping. An optical resonator includes a solid laser crystal to be excited by the incident of a laser beam to oscillate a fundamental wave and a pair of fundamental wave reflective coats arranged at the opposite sides of the solid laser crystal. A wavelength conversion element converts the fundamental wave into a plurality of harmonics. The wavelength conversion element is so arranged in the optical resonator that the optical axis of at least one of the plurality of harmonics, generated in the optical resonator is made different from that of the fundamental wave and the at least one harmonic whose optical axis is made different is output substantially in the same direction as the other harmonic. By this construction, it is possible to stabilize a harmonic output and utilize a plurality of harmonics without increasing the number of parts.