Abstract: A wiring board comprising an insulating substrate containing at least an organic resin, a plurality of electrically conducting wiring layers formed on the surface and/or inside of said insulting substrate, and via-hole conductors formed in said insulating substrate in order to electrically connect the plurality of electrically conducting wiring layers, wherein said via-hole conductors contain an organic binder as well as a Cu—Sn intermetallic compound as an electrically conducting component. The via-hole conductors formed in the wiring board exhibit a high electric conductivity and a large heat resistance, making it possible to very highly reliably connect the electrically conducting wiring layers together.