A method for manufacturing a printed-wiring assembly is provided. The method includes a first step of forming a first pattern of printed wiring extending to an end face of a substrate by copper or silver on the substrate. The method includes a second step of cutting the first pattern into a first portion on the end face side from a predetermined position and a second portion on the inner side of the predetermined position, and the cut surface in the second portion is inclined by a predetermined angle with respect to a surface perpendicular to the substrate. The method further includes a third step of forming a protective layer of the second portion so as to cover the cut surface.