An electron emission device including a first substrate, a second substrate, a gas, a sealant, and a phosphor layer is provided. The first substrate has a cathode thereon, and the cathode has a patterned profile. The second substrate is opposite to the first substrate and has an anode thereon. The sealant is disposed at edges of the first substrate and the second substrate to assemble the first and second substrates. The gas is disposed between the cathode and the anode and configured to induce a plurality of electrons from the cathode, wherein the pressure of the gas is between 10 torr and 10−3 torr. The phosphor layer is disposed on the moving path of the electrons to react with the electrons so as to emit light.