To improve adsorption propertiesof Pb(Ⅱ) onmontmorillonite,porous montmorillonite(PM) is prepared using CaCO₃ porogen and Na-montmorillonite material. The properties of PM are characterized by scanning electron microscopy(SEM),Fourier transform infrared spectrum (FTIR) and X-ray diffraction(XRD), and the adsorption properties of Pb(Ⅱ) on PM are discussed.The experimental results show that PM has abundant pores.With the increase of PH value,adsorption capacity by PM of Pb(Ⅱ) increases first and then decreases at 25℃,and the adsorption capacity is the highest when initial pH is 5.5.The adsorption process accords with the pseudo-second order kinetics model and the adsorption isotherm accords with Langmuir equation. The saturated adsorption capacity is 143.5 mg/g at 25℃,when pH is 5.5.