A power supply system comprising: a power supply device disposed on a vehicle lower portion of a vehicle; a power line electrically coupled to the power supply device, wired inside a hollow coupling member that couples a vehicle upper portion of the vehicle with the vehicle lower portion thereof, and configured to supply electric power from the power supply device to the vehicle upper portion; a power distributor electrically coupled to the power line, and configured to distribute electric power input from the power line to a first load device; a first voltage converter electrically coupled to the power line and configured to convert voltage of the electric power that is input from the power line; and an overhead console disposed on the vehicle upper portion and on a front side in an advancing direction of the vehicle, wherein the overhead console accommodates the first load device, the first voltage converter and the power distributor; characterized by the coupling member being a front pillar disposed on the front side in the advancing direction; a second voltage converter accommodated in the overhead console, electrically coupled to the power line, and configured to convert voltage of the electric power that is input from the power line, wherein the power distributor is electrically coupled to each of the first voltage converter and the second voltage converter and configured to distribute electric power to each of the first voltage converter and the second voltage converter, the electric power converted by the first voltage converter is supplied to the first load device, and the electric power converted by the second voltage converter is supplied to the second load device which is disposed on the vehicle upper portion. a power supply device disposed on a vehicle lower portion of a vehicle; a power line electrically coupled to the power supply device, wired inside a hollow coupling member that couples a vehicle upper portion of the vehicle with the vehicle lower portion thereof, and configured to supply electric power from the power supply device to the vehicle upper portion; a power distributor electrically coupled to the power line, and configured to distribute electric power input from the power line to a first load device; a first voltage converter electrically coupled to the power line and configured to convert voltage of the electric power that is input from the power line; and an overhead console disposed on the vehicle upper portion and on a front side in an advancing direction of the vehicle, wherein the overhead console accommodates the first load device, the first voltage converter and the power distributor; characterized by the coupling member being a front pillar disposed on the front side in the advancing direction; a second voltage converter accommodated in the overhead console, electrically coupled to the power line, and configured to convert voltage of the electric power that is input from the power line, wherein the power distributor is electrically coupled to each of the first voltage converter and the second voltage converter and configured to distribute electric power to each of the first voltage converter and the second voltage converter, the electric power converted by the first voltage converter is supplied to the first load device, and the electric power converted by the second voltage converter is supplied to the second load device which is disposed on the vehicle upper portion.