Al-pillared montmorillonites were prepared by ion exchange reaction and characterized by X-ray diffraction and traditional chemical elemental analysis. The optimum conditions for fluoride adsorption such as vibrating time, sample dosage, pH value and original concentration of fluoride were studied by orthogonal experiments. The stabilities of pillars on pillared montmorillonites were also investigated. The results showed that Al-pillared montmorillonites have high adsorption capacity and adsorption percent. Their adsorption isotherms belong to the Freundlich type.