A multilayer metal film disposed on a base having insulating properties includes a first metal film that is in contact with the base and that is electrically conductive, a second metal film covering the first metal film from a side of the first metal film opposite to the base, the second metal film having resistance to solder leaching, and a catalytic layer disposed between the first metal film and the second metal film, the catalytic layer having a protruding portion protruding toward the second metal film, the protruding portion extending into the second metal film.