The present invention, in a photoelectric conversion device in which a pixel including a photoelectric conversion device for converting a light into a signal charge and a peripheral circuit including a circuit for processing the signal charge outside a pixel region in which the pixel are disposed on the same substrate, comprising: a first semiconductor region of a first conductivity type for forming the photoelectric region, the first semiconductor region being formed in a second semiconductor region of a second conductivity type; and a third semiconductor region of the first conductivity type and a fourth semiconductor region of the second conductivity type for forming the peripheral circuit, the third and fourth semiconductor regions being formed in the second semiconductor region; wherein in that the impurity concentration of the first semiconductor region is higher than the impurity concentration of the third semiconductor region.