To facilitate handling of an electric wire when an on-vehicular battery and an on-vehicular actuator are positioned at a far place and a larger voltage than a voltage of the battery is required for the on-vehicular actuator.

The on-vehicular large power control device is provided with the on-vehicular battery 10 arranged at any one of a front side or a rear side of the vehicle; a voltage raising circuit 13 for raising the voltage of the on-vehicular battery; and a control circuit 14 for controlling the on-vehicular actuator in responsive to the raised voltage of the voltage raising circuit. The voltage raising circuit and the on-vehicular battery are arranged at any one of the front side or the rear side of the vehicle and the on-vehicular actuator is arranged at any other side of the front side or the rear side of the vehicle.