To provide a thermion emission device which includes carbon nanotubes 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 extracting wires arranged around the lattice, and a thermion emission unit. The thermion emission unit includes two electrodes and thermion emission elements. The above two electrodes are connected electrically with the thermion emission elements. The thermion emission elements includes carbon nanotube structural body. There is provided also a method of manufacturing the thermion emission device.