A multilayer wiring board comprising a plurality of conductor patterns stacked with an insulating layer composed of a thermosetting resin interposed between adjacent conductor patterns, wherein the insulating layers are each formed of a pair of film-like thermosetting resin layers and a resin film having a lower coefficient of linear expansion than, and sandwiched between, the thermosetting resin layers, and wherein the electrical connection between the stacked conductor patterns is established by vias formed through the insulating layers. A method of fabricating such a multilayer wiring board is also disclosed.