Abstract—The relationship model of chloride ion content and oxidation peak current was established by the study of curve obtained by using gold electrodes to test cyclic voltammetry in raw milk containing different chloride ion concentrations. The study found that with the increased of chlorine ion content, the potential of the oxidation peak was in positive correlation and the current of the peak increased dramatically. The golden matter appeared in sample liquid. In addition, we observed that corrosion in gold electrode, and the characteristic peak of Au-Cl-1 appeared at 269cm-1 by using SEM and SERS to detect the reaction electrode. The results showed that the gold electrode had the anodized dissolution because of the presence of chloride ion. The prediction model of chloride ion content with a detection limit of 0.05g/L was established by the least square method. The recovery rate and relative standard deviation of the method were respectively from 91.0% to 106.0% and from 3.4% to 4.2%. The method is suitable for rapid detection of milk mixed with salt.