Chitosan is an alkaline polysaccharide containing a large number of primary hydroxyl secondary hydroxyl amino anhydride bonds and other polar functional groups and lone pair electrons. As a kind of natural macromolecule product which is green, cheap, easy to get, biodegradable and has a large number of active functional groups, it has been widely used in many fields. In this paper, the research progress of chitosan and its derivatives in the field of metal corrosion in recent years was reviewed, the advantages of chitosan as corrosion inhibitor were expounded, and the research status and mechanism of chitosan were also described. The structural characteristics of chitosan polymer and its properties as metal corrosion inhibitor were described. The mechanism of chitosan corrosion inhibitor was analyzed. This paper introduces the preparation methods of chitosan derivatives, and classifies them according to different functional groups, including carboxymethyl chitosan, schiff base chitosan, quaternary ammonium salt chitosan, etc., and compares the corrosion inhibition efficiency of different chitosan and its derivatives under different corrosion environments. At the same time, the problems existing in the application of chitosan and its derivatives in antisepsis were summarized, such as poor solubility under neutral conditions and complex synthesis methods of some chitosan derivatives. Finally, the development trend of chitosan and its derivatives in the field of antisepsis was prospected.