A MOS type solid-state image pickup apparatus comprises: a semiconductor substrate having a light receiving surface; a plurality of photoelectric conversion elements arranged in an array manner on the light receiving surface; a plurality of layers of wirings that goes across the light receiving surface and are stacked above the semiconductor substrate, the wirings being connected to signal reading circuits each of which is provided in association with each of the photoelectric conversion elements; and an insulation layer interposed with the layers of wirings, wherein a first wiring, which connects to a gate of a MOS transistor forming a part of each of the signal reading circuits, is provided in a lower one of the layers of wirings, and a second wiring, which connects to a source or drain of the MOS transistor, is provided in an upper one of the layers of wirings.