The present disclosure provides a vehicle-mounted display system and a vehicle. The vehicle-mounted display system includes a transparent projection screen and a projector configured to project an image onto the transparent projection screen. A first polarizer is attached onto a lens of the projector, and a second polarizer is attached onto the transparent projection screen. The second polarizer has a polarization transmission direction crossing a polarization transmission direction of the first polarizer at such an angle as to enable a light beam from the projector and passing through the first polarizer and the second polarizer to be of an intensity smaller than an intensity of a light beam capable of being recognized by human eyes. The second polarizer has a polarization reflection direction perpendicular to its polarization transmission direction, so as to reflect a light component in the polarization reflection direction.