To manufacture an electron emitting element having uniform and satisfactory electron emission characteristics, by causing carbon or a carbon compound to be accumulated by applying a voltage between element electrodes in the presence of carbon monoxide after the electron emitting part is formed.

Element electrodes 4, 5 of printed conductors or the like composed of a metal or an alloy, a metal oxide and glass or the like, are formed on a substrate 1 of glass or the like containing reduced quantity of impurities such as quartz glass, Na or the like, and a conductive film 3 of a fine-grained film consisting of fine grains is formed by connecting these element electrodes 4, 5 with each other. Subsequently, an electron emitting part 2 is formed by processing the conductive film 3 by current carrying. The electron emitting part 2 includes a crack and electron emission occurs from the vicinity of this crack. Nextly, a voltage being applied between the element electrodes 4, 5 in the presence of carbon monoxide, carbon or a carbon compound being accumulated on the electon emitting part 2 and in the vicinity thereof, a planar electron emitting element is thus formed.