An endoscope system 1 includes an image pickup device 11 that is inserted into a subject and picks up an image inside the subject and a memory 22 that records an intra-subject image acquired by the image pickup device 11 and position information of the image pickup device 11 in association with each other. The endoscope system 1 includes an image generating section that applies, to the intra-subject image, when it is determined that a release signal is generated as a predetermined trigger signal, predetermined processing for distinguishably displaying the intra-subject image at a time when the release signal is generated and generates an image obtained by pasting the intra-subject image onto a model image of a predetermined organ.