Phosphate coating is a kind of water-based inorganic coating formed by adding metal and metal oxide into phosphate binders. Due to the advantages of high mechanical strength, good protective performance and high adhesion to the substrate, warm hardened phosphate coating has been widely used in aerospace, navigation, automobile and other industrial fields. Compared with the metal coating and organic coating, phosphate coating has attracted more and more attention due to their unique advantages. The components of phosphate inorganic coating were introduced, and its applications in corrosion protection, anti-abrasion, friction reduction, and heat insulation were summarized. Firstly, the functions of binder, curing agent and aggregate in coatings were described in detail, and the research progress of each component was also discussed. Then, the theory of phosphate coating curing at home and abroad was reported, and the film forming mechanism at high temperature and room temperature was analyzed. Afterwards, in view of the shortcomings of the phosphate coating, such as high curing temperature, high brittleness, poor toughness and surface defects, the modification treated by organic solvents, retarders, silica sol and graphene was summarized. Finally, the development tendency of the phosphate coating was prospected, and it was pointed out that the preparation of curable coatings at room temperature and organic-inorganic composite coatings would be the focus of future research.