A photoelectric conversion apparatus has a plurality of photoelectric conversion elements arranged on a semiconductor substrate, a plurality of wiring layers arranged on the semiconductor substrate through the first and second insulation layers, and a high refractive index region which is arranged in an opening part that is arranged in the interlayer insulation layer so as to correspond to the photoelectric conversion element and has a higher refractive index than the interlayer insulation layers, wherein an area of a cross section parallel to a photoreceiving plane of the photoelectric conversion element in the high refractive index region increases as the position approaches to an upper part of the substrate from a photoreceiving plane of the photoelectric conversion element, namely, as the position approaches to a light-incident plane, and the increasing rate continuously increases with the increase of the area.