Abstract: A method of making terminal nut for ignition plug by plastic working, comprising; first step in which a metallic blank is struck at its end surfaces to flatten the end surfaces in prependicular to axial direction of the blank; second step in which a central conical dent is formed at one end surface of the blank, and forming first bottom-ended hole at other end surface of the blank; third step in which second bottom-ended hole is formed concentrically and continuously from the first bottom-ended hole at the blank to be diametrically lesser than the first bottom-ended hole; fourth step in which the blank is axially contracted to diametrically bulge outward by upsetting; fifth step in which a perforation hole is axially formed at the blank by punching in concentrical relationship with the first bottom-ended hole; sixth step in which the blank is shaved at its bulged portion.