To provide a thermion emission device which includes carbon nano tubes specifically.

The thermion emission device includes a base plate, an insulative base plate and a plurality of lattices formed on the insulative base plate. Each of the lattices includes four electrode leading wires arranged around each lattice and a thermion emission unit. The thermion emission unit includes two electrode and thermion emission elements. The above two electrodes are connected electrically with the thermion emission elements. The thermion emission element includes a carbon nanotube structural body. The carbon nanotube structural body includes at least one carbon nanotube wire.