The electrochemical behavior of interaction between salvianolic acid B (SalB) and bovine serum album in(BSA) was investigated by cyclic voltammetry and square wave voltammetry based on DNA-modified glass carbon electrode (GCE) in 0.01 mol/L phosphate buffer solution (pH 7.4).SalB generated a sensitive oxidation peak of 0-100 V at the DNA modified GCE.After addition of BSA into the SalB solution,the oxidation current decreased and the peak potential shifted positively.The electrochemical parameters,such as the charge-transfer coefficient α and the standard electron-transfer rate constant ks were also changed.The binding number m of 1.71 and the binding constant β of 1.00×108 L/mol were calculated according to the data of the oxidation current,which indicated that SalB could combine with BSA to generate a non-electric complexes with combination ratio of 2∶1.The results were in agreement with that provided by the fluorescence spectrometric method.