Lower detection stability and sensitivity of laser-induced breakdown spectroscopy (LIBS) restrict development of the technique. We use an integrated ICCD single and double pulse LIBS system to analyze the Pb element in Pb(NO3)2 solution enriched by the filter paper, to compare the sampling gate width, integral time delay, time delay of two double pulse laser beams and other parameters affecting the spectrum quality, and to determine the best conditions to detect Pb element in water solution by LIBS. The results show that the double pulse has better stability. Under the optimal conditions, the single, double pulse LIBS spectral information of six solution samples with different Pb concentrations is obtained, and the relationship model between the actual Pb concentration and its spectral intensity is built, showing that the LIBS detection limits of trace Pb element are 15.95 μg /mL and 5.48 μg /mL, respectively. The fitting results indicate that the double pulse has a better linear correlation coefficient, detection sensitivity and accuracy. It is suggested that the integrated ICCD dual-pulse LIBS will improve the effect on heavy metal detection in water.