The present disclosure is to provide a slit grating applied in autostereoscopic display apparatus and autostereoscopic display apparatus. The slit grating includes a substrate and a plurality of light-shielding strips arranged in intervals on the substrate; the light-shielding strips is used to shielding incident light; the slit grating further includes a wire grid among a light-transmitting region between the light-shielding strips, and the wire grid is used to transmitting a first polarized component of the incident light and reflecting a second polarized component that is perpendicular to the first polarized component of the incident light. The autostereoscopic display apparatus includes a backlight module, a liquid crystal display and the slit grating. The present disclosure can improve brightness of display device, and achieve cost decreasing and thickness reducing at the same time.