A solid-state laser apparatus including a resonator in which oscillation of laser light occurs. An etalon is provided in the resonator for selecting a predetermined wavelength as a wavelength of laser light to be output from the solid-state laser apparatus. The etalon has at least one surface through which laser light passes, and is arranged so that at least one reflectance of the at least one surface at the above predetermined wavelength is smaller than reflectances of the at least one surface at wavelengths other than the predetermined wavelength. In addition, at least one resonator mirror of the resonator is arranged so that at least one reflectance of the at least one mirror at the above predetermined wavelength is greater than reflectances of the at least one mirror at wavelengths other than the predetermined wavelength.