In order to solve the problem of wear and corrosion for the economizer, and not to impair its thermal conductivity, a graphene composite coating was presented by applying graphene modified enamel and spraying technology. The properties of the graphene composite coating were investigated by scanning electron microscopy (SEM) observation, the test of static sulfuric acid corrosion, hardness, thermal conductivity and tension. The experimental results showed that graphene composite coating has many advantages, such as compact structure, small porosity, high hardness, good wear and corrosion resistance. Graphene composite coating can effectively protect the matrix material because of its significant performance. Furthermore, thermal conductivity of the graphene composite coating can reach 38 W?（m?K）-1, which is much better than that of the traditional ceramic coating.