A vehicle controller is mounted in a box-shaped manner beneath the floor or on the roof of a vehicle so as to supply electric power to vehicle apparatuses. The vehicle controller is configured with a plurality of functional modules; each of the functional modules has at one side thereof an interface side in which a first interface region where signal-line terminals are arranged and a second interface region where power-line terminals are arranged are separated; in each of the interface sides, the first interface region is disposed at one and the same end and the second interface region is disposed at the other and the same end.