Copper hexacyanoferrate(CuHCF) redox probes were fabricated on the gold electrode surface through electrodeposition.Through the strong interaction of Au-CN bond between CN-(CuHCF) and gold nanoparticles(GNPs)，GNPs were assembled on the CuHCF modified electrode.Then，thiolated adenosine aptamers(APT) was assembled on the electrode surface with Au-S bond for the fabrication of highly sensitive label-free aptamer biosensor used for the determination of adenosine(AD).Electrochemical impedance spectroscopy was used to monitor the self assembly process of the aptamer biosensor.The electrochemical behavior of the aptamer biosensor was studied by cyclic voltammetry(CV) and differential pulse voltammetry(DPV).Effects of the supporting electrolytes and scan rates on the response of aptamer biosensor were investigated.The biosensor showed a good linear relationship for adenosine in the range of 100 fg/mL-50.0 ng/mL，with a correlation coefficient(r) of 0.998 and a detection limit of 45.0 fg/mL.