The invention discloses an anti-peeping film, a manufacturing method thereof, a backlight module, and a display device, which relate to the field of display technology and are used to realize all-round anti-peeping of the display device. The anti-peeping film includes a substrate, the light incident surface of the substrate is provided with a reflective layer, the reflective layer is provided with at least one light-transmitting hole; the light-emitting surface of the substrate is provided with a microlens array; each of the transparent The light holes are respectively corresponding to at least one microlens in the microlens array; the microlens is used to control the exit direction of the light emitted from the light exit surface of the substrate; or, the microlens is used to control The outgoing direction of the light emitted from the light emitting surface of the substrate is deflected toward the axial direction of the microlens. The anti-peeping film, the manufacturing method thereof, the backlight module and the display device provided by the invention are used in the liquid crystal display device.