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The removal of heavy metals such as lead and zinc from wastewaters is necessary,because of their accumulation in living tissues through the food chain as non-biodegradable pollutants [1,2].In this work,the thermodynamics of Ammonium-saturated clinoptilolite removing lead and zinc icons from aqueous solutions at different temperatures were studied.The results showed that the maximum ion exchange capacities of Ammonium-saturated clinoptilolite for lead and zinc ions were found 80.07 mmol/100 g zeolite and 29.94 mmol/100 g zeolite,respectively.Equilibrium sorption data were analyzed by using Langmuir and Freundlich isotherm models.It was showed that Langmuir adsorption isotherm could be a better description of Ammonium-saturated clinoptilolite adsorbing lead ion and Freundlich isotherm models for adsorbing zinc ion.According to the thermodynamic equilibrium principle,the thermodynamics parameters such as enthalpy,Gibbs free energy and entropy changes were also calculated.Thermodynamic investigation indicated that the process of Ammonium-saturated clinoptilolite adsorbing lead and zinc icons was a spontaneous endothermic reaction,and high temperature would be beneficial to the adsorption reaction.This paper summarized that Ammonium-saturated clinoptilolite could be used as an efficient ion exchange material for the removal of lead and zinc ions from industrial wastewaters.