A stereoscopic image display device includes: a display panel in which pixels each constituted with N×N pieces (N is a natural number of 2 or larger) of sub-pixels colored in M (M is a natural number of 1 or larger) primary colors are arranged in matrix; and an optical separation module in which optical elements which distribute exit light from each of the pixels according to parallax images in a first direction and a second direction along layout of the pixels are arranged by being corresponded to each of the pixels. The neighboring sub-pixels within the pixels are of different colors, array pitches of the sub-pixels are uniform in the first and second directions, same numbers of the parallax images are displayed for the first direction and the second direction within the pixels, and numbers of the sub-pixels in different colors within the parallax images are equivalent.