To increase spatial resolution by observing a sample based on saturated fluorescence components. A fluorescence microscope according to the present invention includes: a laser light source 10 emitting laser light as excitation light; an objective lens 13 focusing the laser light and applying the focused laser light to a sample 14; a detector 22 detecting fluorescence generated in the sample 14 with the laser light; and a stage 15 scanning the sample 14 while moving the sample 14 relative to the laser light, wherein the laser light is applied to the sample with varying intensities such that saturation of fluorescence occurs at the maximum intensity of the laser light, and fluorescence is detected with the detector in accordance with intensity of the laser light, and the sample is observed based on the saturation components of fluorescence.