In order to explain the local air pollution caused by the smoke produced by soldering leaded tin wire with electric soldering iron, an experimental system based on laser induced breakdown spectroscopy was designed to analyze the smoke produced by soldering leaded tin wire with electric soldering iron, and the characteristic spectral line of heavy metal lead was found in the smoke spectrum. Lead was quantitatively analyzed by internal standard method, and the detection limit of lead was 19.35×10-5 by fitting the curve. By analyzing the correlation between the plasma temperature and electron number density of lead, the validity of the experimental spectrum was verified. The results show that the experimental system and method of scene detection of electric soldering tin wire based on laser-induced breakdown spectrum have advantages of on-line, in-situ and fast when compared with the traditional chemical test method.