A new method using aluminum oxide (Al2O3) as solid-phase extraction coupled with atomic absorption spectrum(AAS) was proposed. The adsorption behavior of Al2O3 nanoparticles towards Cd2+ was investigated by AAS, and the adsorption pH, isotherms as well as capacities were obtained. It was found that the adsorption rates of Cd2+ was more than 98% in pH 8.50~10.00. The adsorption equilibrium data of Cd2+ were well fitted with the Langmuir isothermal equation. The kinetic experimental data correlated well with the pseudo-second-order kinetic model. Adsorption enthalpy of standard (DHq) was 5.23 kJ mol-1, which indicated that adsorption reaction was an endothermal process in the range of being studied temperature. It was sufficient for 1.0mol L–1 HCl to elute Cd2+ on Al2O3 nanoparticles and recovery rate was more than 95%.