A solid-state image pickup device capable of suppressing the generation of dark current and/or leakage current is provided. The solid-state image pickup device has a first substrate provided with a photoelectric converter on its primary face, a first wiring structure having a first bonding portion which contains a conductive material, a second substrate provided with a part of a peripheral circuit on its primary face, and a second wiring structure having a second bonding portion which contains a conductive material. In addition, the first bonding portion and the second bonding portion are bonded so that the first substrate, the first wiring structure, the second wiring structure, and the second substrate are disposed in this order. Furthermore, the conductive material of the first bonding portion and the conductive material of the second bonding portion are surrounded with diffusion preventing films.