A printed wiring board for package-on-package includes a first insulating layer, a wiring layer including a conductor pattern and formed on first surface of the first insulating layer, a second insulating layer formed on first surface side of the first insulating layer, electrodes formed in through holes of the first insulating layer respectively such that the electrodes electrically connect to the conductor pattern and have exposed surfaces exposed from second surface of the first insulating layer, first pads formed on the second insulating layer and positioned to connect an IC chip in center portion of the second insulating layer, second pads formed on the second insulating layer and positioned in outer edge portion of the second insulating layer to connect a second printed wiring board, and via conductors formed in the second insulating layer such that the via conductors electrically connect the first and second pads to the conductor pattern.