To provide a laser light source apparatus which can easily exchange a laser light source apparatus, and to provide a confocal microscope apparatus utilizing the same laser light source apparatus.

The laser light source apparatus 1 is provided with laser light sources 11, 21 and 31 which respectively oscillates laser beams L10, L20 and L30 of different wavelengths; a composite optical system 2 for selecting the light of the predetermined wavelength from among the laser beams L10, L20 and L30, and then compositing a plurality of laser beams to only one laser beam L1; an optical fiber 5 for introducing the laser beam L1, and then propagating this light beam L1 to the external side; and base members 10, 20 and 30 for holding by each pair of the laser light sources 11, 21 and 31 and dichroic mirrors 14, 24 and 34 for selecting the light beam of the predetermined wavelength, capable of mutually loading and unloading with a coupling portion.