A direct type backlight source, a manufacturing method thereof, and a display device are disclosed, the direct type backlight includes a light emitting module including a substrate and a plurality of light emitting units arranged on the substrate; a lens film layer positioned on a light emitting side of the light emitting module, one side of the lens film layer away from the substrate is provided with a plurality of collimating structures arranged in an array, each of the collimating structures includes at least one convex surface structure, and the plurality of collimating structures are in one-to-one correspondence with the plurality of light emitting units.