As an inert overlay coating, enamel coating can be compatible with most metal parts and provide excellent corrosion protection effect. However, the property of high temperature softening and inherent brittleness of enamel coating limit its application at high temperature and in thermal shock environments. The current research progress in solving contradiction between enamel sintering temperature and service temperature as well as the poor thermal shock resistance during thermal cycling was reviewed. Firstly, the method system of improving the coating application temperature without changing its melting and sintering temperature through composite ceramic particles and controlling the enamel/ceramic interface reaction was introduced. Then, the factors affecting the thermal shock resistance of enamel coating were analyzed, including the thermal expansion coefficient of enamel, binding of enamel/alloy interface, mechanical properties of enamel, etc. Due to the Si-O network structure, it is hard to enhance thermal shock resistance of enamel coating largely by thermophysical and mechanical properties modification. Based on this face, self-healing metal-enamel composite coating is proposed, which can fundamentally solve the problem of enamel cracking and spallation.