To user the same pallets and the same metal masks to reduce the types of jigs and also to contrive to enhance the efficiency for mounting components by a method wherein both surfaces of printed-wiring boards are respectively made to arrange on an end material and the end material is made to invert.

Circuit constituent components are mounted on each of the surfaces and rears of printed-wiring boards 1. An end material 3 has coupling parts 4 for coupling the boards 1 with each other. Metal masks are respectively mounted on one part of each printed-wiring board 1, solder in semi-molten state is applied in one direction of the boards 1 and the metal masks are demented from the boards 1. Thereby, the components are mounted on each of the surfaces and rears of the boards 1. Then, the outer end surface of the end surfaces of the end material 3 is made to invert to mount respectively the metal masks on one part of each printed-wiring board 1, solder in semi-molten state is applied in one direction of the boards 1 and the metal masks are demented from the boards. Thereby, the components are respectively mounted on the surfaces and rears of the boards 1 provided on the other end surface of the end material 3.