A soldering iron capable of eliminating static charges accumulated on an operator or materials to be soldered simply without using no particular charge elimination device, the soldering iron comprising a combustion catalyst for complete combustion of a gas mixture of a fuel gas and air, a soldering iron tip heated by the combustion catalyst, a gas conduit for exhausting a combustion exhaust gas from the combustion catalyst along the outer circumference of the soldering iron tip toward the top end, and an electric conduction mechanism for electrically connecting an operator for conducting soldering and the soldering iron tip, fuel gas combustion products which are ionized and forming steams upon catalytic combustion contributing to charge elimination.