The aim of this research is to figure out an activated zeolite ability to immobilize Pb element in liquid sample. The zeolite was made into powder with size of about 400 mu m and was activated by NaOH with different concentrations of 0.5, 1, 1.5 and 2 M. Prior to being analyzed by commercial Laser-InducedBreakdown Spectroscopy (LIBS) technique, 0.05 gram activated zeolite of each concentration were soaked into 10 ml solution containing 100 ppm of Pb and then heated and stirred until become dry powder. The powder was then made into a pellet. After being analyzed by LIBS, activation by 1.0 M NaOH was the optimum condition for zeolite to immobilize Pb in solution. The minimum concentration of Pb in liquid sample which could be immobilized by this method was about 5.86 ppm.