Cerium oxide-Tannic acid (CeO2-TA) nanocomposite were used for preconcentration of Pb2+ followed by electrothermal atomic absorption spectrometry. Cerium oxide nanoparticles were synthesized by microwave method and modified by tannic acid to produce CeO2-TA nanocomposite. In order to optimize the experimental conditions, Response surface methodology based on central composite design was used. The obtained results show that the calibration curve was linear in the range of 0.025-1.5 mu g L-1 Pb2+. Also, the accuracy of the method was validated by the analysis of certified referenced material. Finally, the proposed method was applied for determination of Pb2+ in different real samples.