A method for fabricating a carbon nanotube field emitter array is disclosed, which has the steps of (a) providing a substrate; (b) forming a cathode layer having a first pattern on the substrate; (c) forming an opaque insulating layer having a second pattern on the substrate, wherein a predetermined part of the cathode layer is exposed; (d) forming a gate layer having the second pattern on the opaque insulating layer; (e) forming a carbon nanotube layer on the entire top surface of the substrate; and (f) exposing the carbon nanotube layer to a light beam coming from the backside of the substrate.