Abstract: A clear image unaffected by the brightness of the projection environment. The projection screen according to the present invention is a projection screen for projecting thereupon narrow-band tricolor wavelength band light to display an image, and comprises an optical thin film (3) which has high reflection properties regarding the narrow-band tricolor wavelength band light, and has high transmission properties regarding at least visible wavelength band light other than the wavelength band light, on a screen base (2). With the projection screen according to the present invention configured as above, the optical thin film (3) serves as a so-called band filter. That is to say, the optical thin film (3) particularly reflects narrow-band tricolor wavelength band light and transmits light of other wavelengths, thereby functioning as a narrow-band tricolor wavelength bandwidth filter acting to separate these.