A simple and sensitive electrochemical aptamer sensor was developed for the determination of environmental hormone bisphenol A(BPA).Nanoporous Au(NP-Au) was first deposited on the glassy carbon electrode(GCE) surface by electrochemical deposition,followed by one-step electropolymerization synthesis of polythionine(PTH) and aptamer(APT).The PTH was used as a redox electrochemical probe and the immobilization matrix for APT.Then,BSA as a blocking agent was used to prevent non-specific adsorption.The electrochemical behavior of the GCE/NP-Au/PTH+APT/BSA aptamer sensor was studied by DPV method.The GCE/NP-Au/PTH+APT/BSA sensor showed a good linear range of 10.0 fg/mL-1.0 ng/mL for BPA with a detection limit of 5.3 fg/mL.The GCE/PTH+APT/BSA sensor as reference showed a linear range of 10.0 fg/mL-1.0 ng/mL for BPA with a detection limit of 90 fg/mL.The experimental results showed that the introduction of NP-Au could effectively improve the sensitivity.The GCE/NP-Au/PTH+APT/BSA sensor had the advantages of high selectivity and low detection limit.