An electron emission device and an electron emission display having the electron emission device. The electron emission device includes a substrate, a cathode electrode disposed on the substrate, and an electron emission region electrically connected to the cathode electrode. The cathode electrode includes a sub-electrode disposed on the substrate, a sub-insulation layer disposed on the sub-electrode, a main electrode disposed on the sub-electrode and having an opening for exposing a portion of the sub-insulation layer at each of a plurality of unit pixels, a plurality of isolation electrodes disposed on the sub-insulation layer in the opening of the main electrode and spaced apart from the main electrode, and a resistive layer disposed between the main electrode and the isolation electrodes to electrically connect the main electrode to the isolation electrodes.