A field emission cathode capable of emitting electrons under a low voltage. Lead-out electrodes are formed on an insulating layer and openings are formed at a lamination between the insulating layer and each of the lead-out electrodes. Emitters each are arranged in each of the openings. The insulating layer is provided on a lower surface thereof with a photoresist layer modified by heating. The modified photoresist layer is electrically connected through a resistive layer to a cathode electrode. The cathode electrode is formed in a pattern on a cathode substrate made of glass or the like. The emitters each are constituted by a distal end of each of projections of the modified photoresist layer exposed from the insulating layer. The photoresist is modified by heating, resulting in being provided with electrical conductivity and exhibiting stable electron emitting characteristics under a low voltage.