An application device for marking wires and cables. The application device includes a foil storage for a printing foil ribbon and a protective foil ribbon. The device also has a printer for imprinting the printing foil ribbon. The printing foil ribbon and the protective foil ribbon which is pressed against the printing foil ribbon after the printing foil ribbon has been imprinted are cut to a marked length in a foil and cutting receiving member and, after the wire to be marked has been sheated with the ribbon to form a closed sleeve, the printing foil ribbon and the protective foil ribbon are welded together.This makes possible a subsequent marking of wire without having to disconnect already connected wires. The marking is protected against ambient influences by the protective foil and can be made at the location where the wire is installed.