Disclosed is a power supply unit reducing deterioration of power loss caused by cables. A connector connecting a power line L11 connected to a battery and a plurality of ramp loads is attached to a holder housing at least one of the plurality of ramp loads. The connector is provided with: a pressure-bonding power source terminal to which the power line L11 is connected and power is inputted, a first branch circuit branching one power line inputted from the pressure-bonding terminal into a plurality of branch lines, a plurality of tub-like power source terminal, pressure-bonding power terminals each connected to the plurality of branch lines branched by the first branch circuit and outputting power to each ramp load; and a housing housing them.