[en] The adsorption of "9"0Sr from aqueous solution by montmorillonite or vermiculite, and the effect of experimental conditions on the adsorption were investigated. The preliminary results showed that montmorillonite and vermiculite were both efficient absorbent for "9"0Sr and more than 96% or 98% of the total "9"0Sr could be removed by montmorillonite or vermiculite of 20 g/L from "9"0Sr solution of 20 kBq/L(Co). The adsorption equilibrium was achieved within 30 min and 2h, and the suitable pH ranged 2-12 and 3-12. No significant differences on "9"0Sr adsorption were observed at 0-50℃ by these two natural absorbents. In this time, the adsorption rate decreased with the increase of "9"0Sr concentration in the range of 1-200 kBq/L and the adsorption behavior accorded to Langmuir isothermal adsorption. Furthermore, the adsorption rate both increased efficiently on montmorillonite and vermiculite modified by 1-2 mol/L HCl. About 98% of adsorbed "9"0Sr could be desorbed by 10 mL of 2 mol/L HNO_3. (authors)