To provide an electron emitting source that is hard to receive ion damages, thereby having a long lifetime.

The electron emitting source is an electron gun for an electron beam vapor deposition device, an electron beam welding device, or an electron beam machining device formed of carbide of one or more kinds of metal elements selected from a group composed of Ta, Hf, Nb, and Zr. In this electron emitting source, the acceleration voltage of an electron beam is 10 kV or higher. The electron emission source formed of carbide of one or more kinds of metal elements selected from the group composed of Ta, Hf, Nb, and Zr is mounted to the electron beam vapor deposition device, the electron beam welding device, or the electron beam machining device.