Abstract: The fluorine-containing wastewater discharged from industrial production has great harm to the environment and human body. In this study, three kinds of natural aluminosilicate minerals, diaspore, gibbsite and kaolinite, are used as adsorbents to explore the feasibility of their adsorption of fluorine ions and the mechanism of defluorination. The single factor condition test showed that kaolinite had the best adsorption efficiency for fluoride ion. The removal rate of fluoride ion can reach 82.44% and the concentration of fluoride ion can be reduced from 150 mg/L to 26.34 mg/L under the optimum reaction conditions of granularity of Kaolinite -18 μm, dosage of 10 g/L, pH = 13, reaction time = 10 min and reaction temperature 25 ℃. Kinetic fitting showed that the removal of fluoride ion by kaolinite accorded with quasi-second-order kinetics with theoretical capacity value Q_e=8.0244 mg/g. The adsorption isotherms show that the reaction conforms to Freundlich model and belongs to single layer adsorption. XPS analysis shows that fluoride ion exchanges with hydroxyl groups in kaolinite, and Al-F bonds are formed on the surface of kaolinite, thus achieving the purification of fluoride-containing wastewater.