The work aims to further develop fish scale collagen and expand the application scopes of fish scale collagen. The structural characteristics of fish scale and fish scale collagen were briefly described. Combined with the research and application status of fish scale collagen, the analysis and comparison of the extraction methods for fish scale collagen were emphatically conducted. Moreover, the applications of fish scale and fish scale collagen in medicine, food, chemical and other fields were summarized. Due to the excellent performance of fish scale collagen, the research on fish scale collagen is a hot topic in food, medical and chemical fields both at home and abroad. The research field and application scope of fish scale collagen will continue to expand in the future, which has important practical significance for the development of national economy and the maintenance of green environment.