A principal object of the present invention is to provide efficiently an electron-emitting element. The electron-emitting element includes: (a) a substrate, (b) a lower electrode layer provided on the substrate, (c) an electron-emitting layer provided on the lower electrode layer, and (d) a control electrode layer so disposed as not to be in contact with the electron-emitting layer, wherein the electron-emitting layer includes an electron-emitting material for emitting electrons in an electric field, (1) the electron-emitting material being a porous body having a 3D-network structure skeleton, (2) the 3D-network structure skeleton being composed on an inner portion and a surface portion, (3) the surface portion comprising an electron-emitting component, (4) the inner portion being occupied by (i) at least one of an insulating material and a semiinsulating material, (ii) an empty space, or (iii) at least one of an insulating material and a semiinsulating material and an empty space.