A printed wiring board includes a first resin insulating layer, a first conductor pattern including first mounting pads formed on the first resin insulating layer, and a wiring structure positioned on the first resin insulating layer and including a second resin insulating layer and a second conductor pattern such that the second resin insulating layer and second conductor pattern are positioned adjacent to the first conductor pattern and that the second conductor pattern includes second mounting pads. The second mounting pads are embedded in the second resin insulating layer such that the second mounting pads have mounting surfaces exposed on an exposed surface of the second resin insulating layer, and the first mounting pads have mounting surfaces such that the mounting surfaces of the first and second mounting pads are formed on a same plane.