To provide an electron emission element capable of obtaining a sufficient emission current, reducing scattering of an electron beam on a side wall of an opening, reducing a beam diameter of an emission electron, and maintaining a beam diameter as a pixel to be small, and enabling to manufacture easily.

The electron emission element is structured by forming a gate electrode 14 and a cathode electrode 12 on a substrate 11, and a focusing electrode 16 on the same plane with the cathode electrode 12 or closer to the substrate 11. A space W2 between the cathode electrode 12 and the focusing electrode 16 is narrower at a pixel end part than at a pixel center part.