A printed wiring board includes a first insulating layer, a first conductor layer formed on first surface of the first insulating layer, a second conductor layer formed on second surface of the first insulating layer, a first via structure formed in the first insulating layer such that the first via structure is connecting the first and second conductor layers, a second insulating layer formed on the second surface of the first insulating layer such that the second conductor layer is embedded into the second insulating layer, a third conductor layer formed on the second insulating layer, and a second via structure formed in the second insulating layer such that the second via structure is connecting the second and third conductor layers. The second conductor layer includes a dedicated wiring layer which transmits data between two electronic components to be mounted to the first surface of the first insulating layer.