Disclosed is an electron emission device and an electron emission display using the same, wherein the electron emission device has an improved structure for focusing an electron beam. The electron emission device comprises: first and second electrodes formed on a plate and spaced from each other by a predetermined distance; an insulator formed on the entire area of the plate and formed with an opening through which a portion of the first electrode between the first and second electrodes is at least partially exposed; an electron emitter formed on a predetermined region of the first electrode and exposed through the opening; and a third electrode formed on the insulator and connected to the second electrode, wherein a voltage difference between the first and second electrodes causes the electron emitter to emit an electron and the emitted electron is focused by the third electrode.