An object of the invention is to provide a PCB transformer having plural output channels, which can suppress a voltage fluctuation in each output channel to supply a stable output without the need for a larger body, even though an input load fluctuates. The PCB transformer include, a core having a core axis, a first layer including a winding for each input line separately wound around said core as plural input coils spaced from each other along the core axis, and a second layer including a winding for an output line corresponding to each output channel separately wound on said first layer as plural output coils spaced from each other along the core axis. One of the input coils and one of the output coils are disposed in one of winding regions defined along the core axis. In each the winding region, one coil having a narrower width of the input coil or the output coil is disposed within a width of another coil along said core axis.