The open circuit potential, polarization resistance and corrosion current density of bare steel bars and coated steel bars of magnesium oxychloride reinforced concrete in different environments were studied by Z350 electrochemical workstation, and the corrosion products were analysed by scanning electron microscopy(SEM) and X ray diffraction(XRD). The results show that Zinc(XMT) coating can protect steel bars from corrosion in different environments. The corrosion current density of coated steel bars in water, chloride solution and sulfate solution in magnesium oxychloride reinforced concrete is only 1/35,1/43 and 1/19 of that of bare steel bars. There are loose porous layered and massive corrosion products on the exposed steel bars surface of the magnesium oxychloride reinforced concrete, while only pitting corrosion exists on the surface of the coated steel bars. It can be seen that the XMT coating has a certain anti corrosion effect on the steel bars in the magnesium oxychloride reinforced concrete.