A high reliability emission source is constructed to secure the ohmic contact between a carbon nanotube and an electrically conductive base material, so as to ensure sufficient joining strength, and to provide for easy beam shaft adjustment. An electron microscope for realizing high resolution, high brightness, a reduction in sample damage due to a reduction in acceleration voltage, a reduction in cost and compactness, and an electron beam drawing device for realizing high definition, high efficiency, a reduction in cost and compactness in comparison with the conventional device, is achieved by using this high reliability emission source. In the emission source, the carbon nanotube is attached to the tip central portion of the electrically conductive base material through an electrically conductive joining material or an organic material by carbonization-processing the organic material by heat treatment, or by diffusive joining.