PROBLEM TO BE SOLVED: To observe by a fluorescence image with high quantitativity by sufficiently removing dependency on a distance or the like remaining in an image subjected to division processing.SOLUTION: The fluorescence observation device 1 is provided. The fluorescence observation device 1 includes: an illumination part 4 equipped with a light source 3 emitting illumination light and excitation light a fluorescence image capturing part 18 which captures an image of fluorescence generated in a subject A to acquire a fluorescence image G a return-light image capturing part 17 which captures an image of return-light returning from the subject A to acquire a return-light image G a preprocessing part 23 for generating a fluorescence image G for a correction and a return-light image G for a correction by multiplying at least one of the fluorescence image Gand the return-light image Gby a coefficient which keeps distance characteristics of fluorescence intensity obtained with respect to a standard specimen in advance directly proportional to distance characteristics of return-light intensity and a fluorescence image correction part 24 for dividing the fluorescence image G for a correction generated by the preprocessing part 23 by the return-light image G for a correction.
