PURPOSE: To facilitate solder-welding work by providing a heat generating part where a handle part is covered with a heat insulator and a heat nongenerating part facing the heat generating part where a handle part provided with a function to sandwich objects to be solder-welded is covered with a heat insulator,

CONSTITUTION: When a power source plug 6 is connected with an electric outlet, the heat generating part 1 generates heat. The handle parts 5 are held in the manner to hold the tweezers and the objects to be solder-welded are sandwiched and welded between the heat generating part 1 and the heat nongenerating part 2. When the force to hold the handle parts is loosened, the heat generating part and the heat nongenerating part are opened by a spring 4 and the sandwiched objects to be solder-welded are released. Consequently, solder-welding work can be easily performed by giving a function to sandwich the objects to be solder-welded to the soldering iron.