Observation is performed by using a fluorescent light image of high quantitativity obtained by sufficiently eliminating the dependency, which remains in an image obtained by division, on distance or the like. Provided is a fluorescence observation device (1) that comprises: an illuminating unit (4) including a light source (3) for irradiating an illumination light and an excitation light a fluorescent light image capturing unit (18) for image-capturing a fluorescent light occurring on a subject (A) to acquire a fluorescent light image (G2) a returning-light image capturing unit (17) for image-capturing a returning light, which has returned from the subject (A), to acquire a returning-light image (G1) a pre-processing unit (23) for multiplying at least one of the fluorescent light image (G2) and the returning-light image (G1) by a coefficient for which a mutually proportional relationship is established between a distance property of fluorescent-light intensity and a distance property of returning-light intensity, which have been acquired for a standard sample beforehand, thereby generating a correction-use fluorescent light image (G2") and a correction-use returning-light image (G1") and a fluorescent light image correcting unit (24) for dividing the correction-use fluorescent light image (G2") by the correction-use returning-light image (G1"), both of which have been generated by the pre-processing unit (23).Une observation est réalisée par utilisation dune image de lumière fluorescente de quantitativité élevée obtenue par élimination de manière suffisante de la dépendance, qui reste dans une image obtenue par division, à la distance ou analogue. Linvention concerne un dispositif dobservation de fluorescence (1) qui comprend : une unité déclairage (4) comprenant une source de lumière (3) pour émettre une lumière déclairage et une lumière dexcitation une unité de capture dimage de lumière fluorescente (18) pour capturer une image dune lumière fluorescente se produi
