Abstract: After being stimulated by external factors, the coating damage and the corroded sites of the metal can be self-warned and indicated, which is convenient for timely treatments of the corroded sites, avoiding greater damage to materials due to corrosion. On the basis of comprehensive literature search about the study over the preparation and performance of metal surface self-warning coatings (color performance, fluorescence performance, mechanical damage triggering performance), the different warning mechanisms (color mechanism, fluorescence mechanism, mechanical damage triggering mechanism) are summarized and analyzed.