A metal wiring bonding structure 100 comprises contacts 753 of connection FPC 75 and heater lands 46 of a sheet heater 30 to be bonded by a solder bonding member 766. A connection FPC 75 includes contact opposed lands 754 famed of metal and disposed at positions respectively opposed to the plurality of contacts 753 on a surface of a support layer 751 opposite from a surface on which metal wires 750 are provided, and through holes 755 penetrating the contact opposed lands 754, the support layer 751, and contacts 753. Solder bonding members 756 cover surfaces of contact opposed lands 754 and are filled inside through holes 755 and in a bonding space C.