Provided is a time switch capable of allowing a user to readily set up or change a schedule. For this purpose, a chassis 30 of the time switch 10 has same size (i.e., two-row-module size) as that obtained by arranging two three-module sized implanted type wiring devices in two lines along a minor width direction, and installation frame pieces 38 are protruded from both of upper and lower side walls. In addition, each installation frame piece 38 has a long hole 38a for inserting a box screw fastened to the implanted type box (not shown) implanted on the installation surface or a fastener hole combined with a fastener. Furthermore, decoration covers 33 and 34 are installed in the front side of the chassis 30, and manipulating buttons 45a to 45f of the setup manipulation unit for setting up a time schedule having a set of an address corresponding to the control target load, and a control time and a control item for the load are provided in the decoration cover 33 functioning as a manipulation face of the setup unit 10a.