Abstract: In this paper, the electrochemical corrosion behavior of hot-dip 55%Al-Zn-1.6%Si coat in ammonia water was investigated through the static full immersion, examination of corrosion membranes under microscope and measurement of electrochemical impedance spectroscopy. It is concluded that 55%Al-Zn-1.6%Si coating is corrosion-resistant in ammonia water.