A laser microscope is provided which includes a laser light source, a first optical fiber through which the ultrashort pulse laser light propagates while being positively chirped, a negative dispersion optical system that negatively chirps this propagated laser light, a second optical fiber through which the laser light that has passed through the negative dispersion optical system propagates while being positively chirped, a microscope body that further positively chirps this propagated laser light and irradiates a specimen with the resultant non-chirped ultrashort pulse laser light. The negative dispersion optical system includes a negative dispersion adjuster that adjusts the amount of negative dispersion according to the change in wavelength of the ultrashort pulse laser light outputted from the laser light source or the change in the amount of positive dispersion in the microscope body.