Abstract: Surface water in many regions of China is affected by the soil or water background value, and the concentration of fluoride exceeds 1.0 mg/L, which is higher than the Class Ⅲ water specified in the Environmental Quality Standard for Surface Water (GB 3838-2002). In order to reduce fluoride in surface water and recover adsorption materials, magnetic Al-MOF@Fe₃O₄ was prepared by hydrothermal method. The morphology and composition of the adsorbents were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and porosity analyzer (BET). The results showed that Al-MOF@Fe₃O₄ had irregular shape, rough surface and smaller mesoporous structure, which can provide a large specific surface area to absorb fluoride. The adsorption experiment indicated that the adsorption capacity of Al-MOF@Fe₃O₄ was 75.2 mg/g, which was in accordance with the pseudo second-order kinetic model, indicating that chemical adsorption was the main mechanism of the defluorination process. In addition, higher adsorbent dosage and lower initial concentration enhanced the efficiency of defluorination, but decreased the adsorption capacity. Alkaline conditions were not conducive to the adsorption of fluoride. The effects of co-existing anions on defluorination performance was in the order of CO₃^2- > HCO₃^- > SO₄^2- > PO₄^3- > Cl^-. The study showed that fluoride could be separated from the water rapidly by replacing the surface hydroxyl groups of the adsorbent, and the adsorbent could be efficiently regenerated with NaOH solution. After five cycles of adsorption experiments, the composite still retained 71.4 mg/g adsorption capacity and good magnetic properties. Finally, defluorination experiments using real surface water showed that the adsorbent effectively reduced fluoride concentration from 1.17 mg/L to less than 0.2 mg/L. In conclusion, Al-MOF@Fe₃O₄ nanocomposite can be used as adsorbent to effectively remove fluoride in surface water.