A multi-view pixel directional backlight module and a naked-eye 3D display device are provided. The multi-view pixel directional backlight module includes at least two rectangular light guide plates closely stacked together. A light-emerging surface of the rectangular light guide plate is provided with multiple pixel arrays. Light emitted by pixels in a same pixel array is pointed to a same viewing angle, and different pixel arrays have different viewing angles. At least one side of each rectangular light guide plate is provided with a light source group. Light emitted by the light source group enters the corresponding light guide plate, then emerges from pixels of respective pixel arrays on the light-emerging surface of the light guide plate, and is totally reflected at positions other than positions of the pixels within the light guide plate. Each of the pixels is a nano-diffraction grating.