The composite coatings of Ni-P chemical deposition and Ni-Co-Mn electroplating were made by the process of first Chemical deposition and last electroplating, and the mechanical properties and hot-corrosion resistance of the coatings were studied through the methods of metallographic observation, nanoindentation, nano-scratch, SEM, and EDS. The results show that the elastic modulus and nano-hardness of the coatings are similar with the electroplating, slightly lower than the chemical deposition. The coatings and substrate is combined well, and the two layers, chemical deposition and electroplating also with good binding force exceeds the maximum measurement value of nano-scratch, while larger than the one between a single electroplating and substrate. The tissue density of the chemical deposition and the electroplating is higher than the substrate, also the anti-hot corrosion resistance and oxidation resistance, and chemical deposition shows better than electroplating. First chemical deposition and last electroplating process is with better binding force than single electroplating process before and after hot corrosion, and is with faster coating growth rate than single chemical plating.