The fluorescence endoscope

PROBLEM TO BE SOLVED: To provide a fluorescent endoscope whose insertion tube end can make a sufficient approach to a part under observation without causing a situation of pick-up impossibility and further enable easy correction of received fluorescence intensity as well as simple exchange of an excited light cut-off filter. SOLUTION: A fluorescent endoscope, comprising: an insertion tube 10 which is to be inserted into a living body; a light-transmitting optical system consisting of a light guide 30 which is included in the insertion tube 10 to irradiate the inside of the living body with excited light L1, etc.; and a light receiving optical system consisting of an image pickup element which is included in the insertion tube 10 to receive fluorescent light generated at the living body in response to irradiation with the excited light L1, etc.; is further provided with a cap frame 20 consisting of a collar body 21 whose flat front end part 21a is located with a predetermined distance from the top of the insertion tube and whose rear end part 21b is detachably mounted on a top part of the insertion tube 10, and a filter 23 for blocking part of the excited light L1 which is going toward the light receiving optical system.