A printed wiring board including a substrate having a first surface and a second surface on the opposite side of the second surface, a first conductive circuit formed on the first surface of the substrate, a second conductive circuit formed on the second surface of the substrate, a magnetic body embedded in the substrate and extending in a thickness direction of the substrate, the magnetic body having a through-hole formed through the magnetic body and extending in the thickness direction of the substrate, and a through-hole conductor formed on an inner surface of the through-hole of the magnetic body such that the first and second conductive circuits are electrically connected to each other through the through-hole conductor.