Nano-TiO2 was employed for the separation and preconcentration of thallium.It was found that the adsorption ratio of thallium ions was more than 98% at pH 4.5 and the desorption ratio reached 99% under microwave irradiation for 3 min at 350 W.The adsorption equilibrium was well described by the Langmuir isotherm model with a maximum adsorption capacity of 4.09 mg/g[(20±0.1) °C].The nano-TiO2 was successfully applied to the determination of element thallium in the certified reference material polymetallic nodule and water samples. It was found that the adsorption ratio of thallium ions was more than 98% at pH 4.5 and the desorption ratio reached 99% under microwave irradiation for 3 min at 350 W. The Nano-TiO2 was employed for the separation and preconcentration of thallium. equilibrium was well described by the Langmuir isotherm model with a maximum adsorption capacity of 4.09 mg / g [(20 ± 0.1) ° C]. The nano-TiO2 was successfully applied to the determination of element thallium in the certified reference material polymetallic nodule and water samples.