Li1.6Mn1.6O4 (LMO) synthesized by microwave assisted hydrothermal method were used to obtain MnO2 center dot 0.5H(2)O ion sieves (HMO) after acid treatment. The HMO-1 prepared with a Li/Mn molar ratio of 4, at 100oC for 1 h under microwave irradiation, exhibits an effective Li+ adsorption capacity of 5.6 mmol center dot g(-1) and a high selectivity to Li+ with an equilibrium distribution coefficient of 12366.44 mL center dot g(-1). Moreover, it shows almost saturated ion-exchange capacity (> 95%) for Li+ extracted/inserted process. Thus HMO ion-sieves with high adsorption capacity and selectivity to Li+ are expected to be a promising application for Li+ selective adsorption from brine, seawater, and aqueous lithium generated in industries.