Corrosion control and protection plays an essential role in ensuring the safety service of metal materials in various complicated environments. As the concept of sustainable development gradually gained popularity, it has become a consensus in the field of metal corrosion and protection to improve or develop green and low-toxicity anti-corrosion materials or corrosion control methods. Carbon dots (CDs) are novel zero-dimensional carbon nanomaterials with various fascinating properties, such as wide raw material sources, various preparation methods, environmental friendliness, facile surface modification and strong fluorescence properties, which have gained widespread attentions. For instance, CDs have been regarded as a kind of promising corrosion inhibitors, possessing abundant groups that can be adsorbed onto the surface of metal substrates to alleviate metal destruction in acidic or neutral corrosive medium. In addition, CDs can be used to construct intelligent corrosion protection coatings with self-healing and corrosion-reporting functions. The work aims to summarize the synthesis pathways and modification methods of CDs and their applications in the field of metal corrosion and protection. The the latest research progress of CDs as corrosion inhibitors and their application in smart corrosion protection coatings, including self-healing and self-reporting coatings, in China and abroad was mainly expounded. As novel corrosion inhibitors, the corrosion inhibition efficiency of CDs was effectively improved when doped with heteroatoms or modified with organic molecules. Therefore, the corrosion inhibition mechanism of heteroatoms doped CDs, organic molecules modified CDs, biomass derived CDs and their advantages and weaknesses were analyzed and discussed in detail. As for the intelligent corrosion protection coating, its design and development generally focused on two aspects: the coating resin matrix and external fillers. The easy modification of CDs surface was conducive to its combination with resin network structures or external fillers. Thus, the design routes and mechanisms of CDs-based intrinsic and external self-healing coatings and corrosion-reporting coatings were introduced. For the intrinsic self-healing strategy, the covalent bonds, hydrogen bonds and van der Waals' force between CDs and resin matrix contributed to the dynamic reversible recovery of damaged coating and the closure of cracks. For the external self-healing mechanism, CDs were loaded by various micro- or nano-containers and then incorporated into organic coatings. In this way, the corrosion reaction between coatings and metal substrates could be effectively suppressed due to the release, diffusion and adsorption of CDs. For the self-reporting function, CDs possessed excellent fluorescence characteristics under UV light irradiation, but its fluorescence could be quenched when reacting with Fe3+ ions generated from steel corrosion. Therefore, the corrosion activity of steel around the damaged coating areas or beneath the intact coatings could be rapidly sensed and reported because of the fluorescence quenching effect of CDs. Finally, the existing problems and the future development prospects of CDs as corrosion inhibitors and their application in smart anti-corrosion coatings are proposed and discussed. In the future, it is necessary to uphold the concept of green and efficiency, further refining the preparation process of CDs. To realize the industrial applications as soon as possible, the key roles of CDs played in corrosion inhibition, self-healing and self-reporting smart coatings should be investigated in-depth. © 2024 Chongqing Wujiu Periodicals Press. All rights reserved.