The present invention provides a projection screen capable of sharply displaying an image even under bright environmental light, of improving brightness distribution and viewing angle, and of providing high image visibility, and a projection system including such a projection screen. The projection screen includes: a polarized-light selective reflection layer that selectively reflects a specific polarized-light component; a substrate that supports the polarized-light selective reflection layer; and a circular Fresnel lens provided on the observation side of the polarized-light selective reflection layer. The circular Fresnel lens controls the optical axis of right-handed circularly polarized light projected on the projection screen so that the light enters the polarized-light selective reflection layer nearly vertically to it regardless of the point and angle at which the light is incident on this layer. The right-handed circularly polarized light incident on the polarized-light selective reflection layer is diffuse-reflected from this layer owing to the scattering properties (the property of diffusing light that is selectively reflected, owing to structural non-uniformity in a cholesteric liquid crystalline structure containing a plurality of helical structure parts whose helical axes extend in different directions) possessed by the polarized-light selective reflection layer, and the reflected light is returned, via the circular Fresnel lens, to a particular observation point at which a viewer makes observation.