A field emission device (10) includes a sealed container (11) with a light-permeable portion (12). A phosphor layer (13) is formed on the light-permeable portion. A light-permeable anode (14) is formed on the light-permeable portion. At least one cathode is positioned opposite to the light-permeable anode. A shielding barrel (16) is electrically connected to the at least one cathode and disposed in the container. The shielding barrel has opposite open ends respectively facing towards the light-permeable anode and the cathode (18, 19). The shielding barrel has an inner surface, and a slurry layer (17) containing conductive nano material is formed on the inner surface of the shielding barrel.