To provide a manufacturing method for a field emitter in which homogeneity and reproducibility of the field emitter can be improved.

A mask is formed on a substrate 1, the substrate 1 is etched in such a degree that the mask 3 is not removed, the surface of the substate 1 is thermally oxidized, and the mask 3 and thermally oxidized are eliminated to manufacture a field emitter in a field emitter manufacturing method, where in a process of etching the substrate 1 to such a degree that the mask 3 is not removed, a part (window-opened part) of the substrate 1 other than the mask 3 is thermally oxidized first, with the heat-oxidized part 4 then etched.