Abstract: As an important radioisotope in nuclear industry and other fields,americium-241 is one of the most serious contamination concerns due to its long half-life(T_(1/2)=433 a) and its high toxicity.Meanwhile,as a rare earth element,europium has similar chemical character to americium.So,(Eu(Ⅲ)) is usually used as a substitute for Am(Ⅲ) when the chemical behavior of ~(241)Am,such as its speciation,translation or migration-sedimentation,should be investigated.In this paper,in order to provide useful reference for adsorption experiment of Am(Ⅲ) on aerated zone soil,the adsorption of Eu(Ⅲ) on the soil,and the effects of various experimental conditions,such as adsorption time,li-(quid)-to-solid ratio,pH,temperature,concentration of Eu(Ⅲ),mass of soil and humic acid,etc.are investigated.The results show that the aerated zone soil is an efficient adsorbent for Eu(Ⅲ).More than 99% of the total Eu(Ⅲ) in solutions could be adsorbed by the aerated zone soil at pH=8 and a liquid-to-solid ratio of 30∶1.The adsorption equilibrium is achieved within 5 hour and the optimum pH ranged 5~9.The relationship between concentrations of Eu(Ⅲ)in aqueous solutions and in soil can be described by the Langmuir adsorption equation.Eu(Ⅲ) uptake on the aerated zone soil is a pH-depen-(dent) process at pH<4,but when pH>4,the adsorption rate of Eu(Ⅲ) on the soil changed(minutely).Humic acid could improve the adsorption of Eu(Ⅲ),while citrate anion and C_2O~(2-)_4 inhibited the adsorption of Eu(Ⅲ) on the aerated zone soil.However,no significant differences on Eu(Ⅲ) adsorption were observed at 10~40 ℃.