In order to study the spectral characteristics of heavy metal plasma in the atmosphere near an industrial zone in Shenyang, double pulse laser-induced breakdown spectroscopy (DP-LIBS) was used to measure and analyze the characteristics of main heavy metal laser-induced breakdown spectra in the atmosphere. By comparing the plasma spectrum of samples excited by single pulse (SP) and double pulse (DP). It was found that DP-LIBS can enhance the intensity of plasma spectrum. The DP-LIBS spectral intensity with the interval time of two pulsed lasers was studied, and the maximum enhancement of the heavy metal plasma spectrum was obtained when the pulse interval was 15 ?滋s. At the same time, the DP-LIBSs technology will also improve the stability of the sample plasma spectrum, and the relative standard deviation of the spectrum line will be reduced from 6% to about 3%. Finally, the changes of electron temperature and electron density with the time interval of double pulse were studied.