By a method of determining the state of an iron tip according to the present invention, in a soldering device including: an iron tip that includes a solder hole into which a solder piece is supplied and that heats and melts the solder piece in the solder hole; a gas supply source that supplies a gas; and a gas supply portion that makes the gas supply source communicate with the solder hole and that supplies the gas from the gas supply source into the solder hole, the total flow rate of the gas flowing through the gas supply portion or a supply pressure is constant, a physical quantity of the gas flowing within the gas supply portion is measured and the measured physical quantity is compared with a previously provided reference value or table such that the state of the iron tip is determined. In this way, it is possible to constantly accurately determine the state of the iron tip.