In an organ-region-indication system incorporated in an electronic endoscope system in which an endoscope image is displayed as a motion image on a monitor in accordance with a video signal produced therein, an organ-region-image data base is formed based on an organ map. A plurality of reference data indicating organ-regions and a plurality of image data representing the organ-region are correspondingly stored in the data base. Still image data is retrieved as referential image data from the video signal at suitable regular time intervals. The data base is searched for image data which coincides with the referential image data after the retrieval of the still image data. Corresponding reference data is displayed on the monitor only when the image data, which coincides with the referential image data, is found by the searching.