A device for displaying in vivo images picked up inside a subject in a time series. The device automatically detects lesion images contained in all in vivo images picked up over the time series. The device displays an elongated display area having a time scale assigned along a longitudinal direction thereof and an indicator which moves along the time scale to indicate a time position in the time scale which corresponds to a current in vivo image currently displayed in a main display area. In response to a detection of the lesion image, the device makes pixels located at a time position in the elongated display area which position corresponds to the lesion image to emit light in a predetermined pixel-display mode. The display mode of the indicator is controlled in response to information on a lesion that is possible to be contained in the current in vivo image.