Fish is a significant source of nutrition for many people globally. Many consumers value this product since it is low-priced and the meat is easily digested. However, the quality of fish degrades easily and rapidly due to enzymatic activity, bacterial activity, and chemical oxidation. Concerns about the health risks associated with using synthetic preservatives have drawn much attention to natural active ingredients that may be able to prolong the shelf life of fresh fish. Chitosan is one of the naturally occurring polymers a preservative to prevent bacterial and oxidation in the fish. This review focused on the effectiveness of chitosan as a preservative for fresh fish and its antioxidant and antibacterial properties. The review also covers the effectiveness of combining chitosan with other bioactive substances in reducing bacterial activity, protein oxidation, and lipid oxidation during fresh fish storage. Chitosan can preserve the freshness of fish during storage. Chitosan has excellent antimicrobial and antioxidant properties. Numerous studies have demonstrated that chitosan's antibacterial and antioxidant activities are directly proportional to its DD and inversely proportional to its MW. However, there is currently insufficient data concerning the relationship between the two features of chitosan and its capacity to preserve fish quality during storage. Chitosan's capacity to keep the freshness of fish can be enhanced by its combination with numerous other natural active compounds. It is intriguing to investigate whether combining chitosan and other natural active compounds is synergistic or additive.