An image display apparatus 4 includes a control unit 15 having an image display controller 15a and an image processing controller 15b to enable an easy recognition of a condition and the like of an imaging target with respect to respective image areas at each imaging point. The image display controller 15a controls to display a time scale indicating an imaging period of a series of intra-subject images, to divide a display area of each time point on the time scale so as to be associated with divided image areas, and to display average colors of divided image areas respectively in divided scale areas separated as a result of the division, the divided scale areas and the divided image areas being associated with each other, respectively. The image processing controller 15b obtains image data stored in the portable recording medium 5 or the storage unit 14 to output to an image processor 13, and controls various image processes on the output image.