A color separation device includes a first color separation member having a first polarization direction changing element and a second polarization direction changing element, and a first polarization separation element, and a second color separation member having a second polarization separation element. Linearly polarized light may be made incident on the first color separation member so as to separate the light into reflected light and transmitted light, both lights having different colors and one of the different colors corresponding to one of three colors, and one of the lights may be made incident on the second color separation member so as to separate the one of the lights into further reflected light and further transmitted light, both further reflected light and further transmitted light corresponding to the other two of the three colors, respectively.