A medical laser apparatus suitable for medical treatment, which is capable
of obtaining a plurality of visible laser beams each having a different
wavelength, but which has an inexpensive structure.A medical laser
apparatus capable of selectively irradiating a plurality of visible laser
beams each having a different wavelength onto an affected part,
comprises: a fiber laser source unit including an excitation light
source, a plurality of fiber lasers for oscillating, by means of
excitation light from the excitation light source, a plurality of
infrared fundamental beams each having a different wavelength and a first
optical switch having an input portion and a plurality of output portions
for selectively switching a transmission path of the excitation light
from the excitation light source to one of the fiber lasers, the fiber
laser source unit being capable of selectively oscillating the
fundamental beams; and a plurality of wavelength conversion elements for
wavelength-converting the fundamental beams, from the fiber laser source
unit, to a plurality of visible second harmonic beams.