In a solid state imaging device having a plurality of pixels arranged in a matrix on a substrate, each of the plurality of pixels includes a photoelectric conversion region and an element separation region separating the photoelectric conversion region. The substrate includes a semiconductor substrate, a first epitaxial layer formed on the semiconductor substrate, and a second epitaxial layer formed on the first epitaxial layer. The photoelectric conversion region and the element separation region are formed over the first epitaxial layer and the second epitaxial layer.