To display a fluorescence screen easy to see by making the coarseness on the observation screen caused by the use of an image intensifier inconspicuous.

This fluorescence observation endoscope indicates the fluorescence image produced by a living body obtained by an endoscope on a television camera, by picking up the image with television cameras 34 and 35 after amplifying the intensity of light with an image intensifier 31. At this time, image signals taken with the above television cameras 34 and 35 are averaged and added for plural frames to form an image for one frame indicated on a television monitor 37.