1. A roll-shaped image-receiving sheet for thermal transfer printing, comprising plural pairs of an image-receiving portion and an optically detectable penetrating hole for registration of the image-receiving portion, each of the image-receiving portion having a size capable of completing a printing of each color in one heating process and being formed continuously along a feeding direction of the roll-shaped image-receiving sheet with an interval therebetween, and each of the optically detectable penetrating hole being formed at portion other than the image-receiving portion in constant arrangement with respect to the corresponding image-receiving portion, including a previously worked part formed on said image-receiving sheet, and a seal part comprising at least a color receptor layer, a substrate sheet and an adhesive layer in this order, and a release sheet put on an adhesive layer so as to be separated therefrom, said seal part being half-cut for peeling off said seal part from said sheet.