To provide an advertising system which allows utilization of window parts, which are not substantially used between tunnel sections, as an advertising area.

The advertising system at train window parts comprises a control device which controls transmission-type display devices 21, 22, 23, 24 and 25 comprising electronic paper sheets and provided in train window parts 11, 12, 13, 14 and 15 so that the display devices display advertisements on the transmission-type display devices, when indicated being in a tunnel section and to make the transmission-type display devices transparent when it is indicated as being in a section other than a tunnel section.