To provide an electron emission device excellent in electron emission efficiency.

In an electron emission device which comprises an electron donating layer 12 consisting of the metal or the semi-conductor, an insulation layer 13 formed on the electron donating layer 12, and a metallic thin film electrode 15 which is faced to the vacuum space formed on the insulation layer 13, and emits the electron by applying the electric field between the electron donating layer 12 and the metallic thin film electrode 15, the insulation layer 13 mainly consists of silicon oxide, contains SiOx in which (x) is 0.5-2 when the atomic ratio is expressed as (x) for the whole layer, and is ≥50 nm in film thickness.