Disclosed is a method of manufacturing a multilayer wiring substrate having a 
principal plane of the substrate and a rear plane thereof, having a structure such that a plurality of resin insulating 
layers and a plurality of conductor 
layers are laminated, and a plurality of 
chip component connecting terminals to which 
chip components are connectable are disposed on the 
principal plane of the substrate. This method has a feature including a plating layer forming process in which product plating 
layers which provide the plurality of 
chip component connecting terminals and a dummy plating layer on the surrounding of the product plating layers are formed on the surface of an exposed outermost resin insulating layer at the 
principal plane of the substrate. This method permits a thickness dispersion of the chip component connecting terminals to be suppressed and permits a connection reliability thereof to the chip components to be increased.