Abstract: An apparatus for bonding flexible printed wires to non-flexible printed wires is provided. The apparatus incudes a heater; and a heating tool heated by the heater and formed to have a heating chip. The heating chip has a height direction and a heating surface directed in the height direction. The heating surface is moved toward the flexible wires to press the flexible wires formed on the non-flexible printed wires. A solder portion is mounted on, at least, ones of the flexible printed wires and the non-flexible printed wires, the heating tool melting the solder portion for a mutual connection between the flexible and non-flexible printed wires when the heating surface of the heating tool is pressed onto the flexible printed wires. The pressing surface is formed as a curved surface having a central part which protrudes outward more than other parts thereof.