Abstract: This paper investigated the galvanic corrosion behavior and laws of AZ91D magnesium alloy coupled with other four metals (Q235 carbon steel, H62 brass, LF21 aluminum alloy, and 356^# cast aluminum) in ethylene glycol solution and the difference before and after inorganic-organic salt compounds were added into the solution as an inhibitor, and then discussed the effect of this inhibitor. It was found that not only uniform corrosion was reduced but also pit corrosion was abated effectively by adding the inhibitor of inorganic-organic salt compounds into the ethylene glycol solution system. By scouting the change of electrochemical parameters and mapping the polarization curves it was found that cathodic control was replaced by anodic control in the process of galvanic corrosion and the effect on anode was more obvious.