The spectroscopy emission characteristics of trace heavy metal lead in water enriched with graphite is studied based on laser induced breakdown spectroscopy technique. With a 1064 nm wavelength NdYAG laser as excitation source, the echelle spectrometer and an intensified charge coupled device are used for spectral separation and high sensitive detection with high resolution and wide spectral range. The characteristic spectral line of 405.78 nm with detection delay time 900 ns and gate time 1600 ns is selected for lead in the experiment. The calibration curve of Pb is plotted based on the different concentration measurement results, and the limit of detection with 0.0665 mg/L is obtained for Pb in water. Carbon as the internal standard element effectively eliminates the spectral instability of the analytical results, and the detection limits and stability are improved.