IN-VEHICLE POWER CONTROL SYSTEM

An in-vehicle power control system includes a first load control unit and a power control device. In the power control device, switch units respectively switch the second conductive paths between an electrically connected state and a not-electrically connected state. A second load control unit predetermines types of switch units, and, if the second load control unit has received, from the first load control unit, a power reduction instruction in which a control method is designated by type, controls the switch units for each type thereof based on the control methods designated by type by the power reduction instruction.