In a timing device for time switch comprising a scale plate rotated at a constant rate and possessing presetting element plug-in portions involving slots, grooves and the like corresponding to time scale on the circumferential part thereof and presetting elements to be inserted to fit into the plug-in portions of the scale plate, this scale plate is composed of a molded plastic guide portion serving to position the presetting elements and to keep the position of each presetting element inserted in the prescribed position, and a metallic body inserted in the plastic guide portion in such that a portion with which the presetting element resiliently engages comes to be a metallic portion.