The preparation of supported adsorbent Al(OH) ₃/SiO ₂ and its adsorption behavior on uranyl ions were studied.The effects of adsorbent quality,solution pH,initial solution concentration,temperature and contact time on adsorption performance were investigated.The adsorption mechanism was preliminarily studied based on adsorption isotherm,thermodynamics,and kinetics.The effects of coexisting ions and fulvic acid on the adsorption properties were also investigated.The results showed that when the adsorbent mass was 0.03 g,pH=5,initial concentration of uranyl ions was 1 mmol/L,temperature was 303 K and contact time was 60 min,the maximum adsorption capacity was 110.4 mg/g,which could be reused four times.The adsorption process of uranyl ion on Al(OH) ₃/SiO ₂ is endothermic and spontaneous.The adsorption of monolayers is dominant,the adsorption behavior conforms to the quasisecondary kinetic model,and the chemical adsorption is the rate control step.