In order to solve the problem of crosstalk and limited number of viewpoints caused by aberrations and geometry in the traditional stereoscopic projection display based on cylindrical lens, a autostereoscopic projection display method based on prismatic reflective grating was proposed. The principle of 3D imaging was analyzed. The autostereoscopic projection display based on prismatic reflective grating was simulated. Compared with traditional autostereoscopic projection display based on cylindrical lens, under the condition of same horizontal video bandwidth, the illuminance of viewing field is ten times, and the crosstalk ratio is 1/5, and there is no secondary viewing zone. The prismatic reflection grating screen was made and the system was set up to carry out experiments. The feasibility of autostereoscopic projection display was verified.