In the solder printer 42 Position solder printing position with respect to the reference mark 18 of the confirmed substrate surface 12 to the reference mark 18 of the substrate surface 12 by the image processing of the multilayer wiring board 11 with the cavity 15 substrate after running the solder printing step of printing collectively or separately solder lands 16 and the land 29 in the cavity 15 of the surface layer 12, in the component mounting machine 43 recognizes the reference mark 18 of the substrate surface 12 by the image processing and substrate surface layer part mounting step of mounting components on the component mounting position by determining the component mounting position of the substrate surface layer 12 on the basis of the position of the reference mark 18 of the substrate surface layer 12, within the cavity 15 of the multilayer wiring board 11 certain solder printing unit 32 and recognized by the image processing based on the location of the particular solder printing portion 32 in the cavity 15 component mounting position in the cavity 15 The decided to run a cavity in the part mounting step of mounting components on the component mounting position.