The work aims to prepare a coating of both high electrical conductivity and infrared emissivity on Mg-Li magnesium alloy by hydrogen evolution method in order to meet the needs of thermal control and electromagnetic shielding in space. Corrosion resistance of the substrate was improved by a series of pretreatment processes (alkali cleaning→acid pick-ling→pre-passivation→electroless plating Ni-P →plating Cu), and adhesion to the following coatings was improved by plating the Cu interlayer. Porous Zn-Ni alloy coating was electrodeposited based on this pretreatment process of Mg-Li alloy. The corrosion behavior of all coatings and adhesion among them were evaluated by virtue of thermal cycle test and electrochemical method. As a result, adhesion of all the coatings completely met the technical standard applicable to satellites in space. The corrosion resistance of Ni-P coating, Cu coating and porous Zn-Ni coating was superior to that of Mg-Li alloy. The synergistic effect of these multi-layer coatings could protect the Mg-Li substrate and increase its corrosion resistance significantly. The outmost layer of porous Zn-Ni coating was composed of Ni2Zn11, NiO and NiS which shows high infrared emissivity of 0.90 and electrical resistance of ＜0.01 mΩ/cm. It can be found that the porous structure can considerably increase the infrared emissivity while maintaining high electrical conductivity of metal alloy coatings.