A projection screen includes a substrate and an optical microstructure. The substrate has a projection area for projecting an image onto the projection area. The projection area includes a plurality of arrayed optical regions. Each of the optical regions includes a first and second optical sub-region with optical characteristics of reflective scattering/transmissive scattering/specular reflection and simple transmission, wherein an area of the second optical sub-region is larger than that of the first optical sub-region. The optical microstructure is arranged on the substrate for guiding the light of the image to a specific direction. The above-mentioned projection screen with two or more optical characteristics, for example, can be at the same time as the front projection screen and the rear projection screen, or allows the user to watch background image behind the projection screen. A projection system including the above-mentioned projection screen is also disclosed. |