A solid-state imaging device with a semiconductor substrate; a pixel formation region in the substrate and including a pixel made of a photoelectric conversion element; and an element isolation portion in the substrate and including an element isolation insulating layer and an impurity element isolation region. The element isolation insulating layer is positioned in a surface of the substrate. The impurity element isolation region is positioned under the element isolation insulating layer and within the substrate. The impurity element isolation region has at least a portion with a width that is narrower than that of the element isolation insulating layer. The photoelectric conversion element extends to a position under the element isolation insulating layer of the element isolation portion.