Abstract: The coronavirus disease 2019 (COVID - 19) pandemic has imposed an enormous burden on health and economy around the world. All public health measures that can reduce the risk of infection and death are of great practical importance. Vitamin D is a fat - soluble vitamin, which plays a certain role in preventing respiratory tract infection, enhancing immune system and maintaining cardiopulmonary function, and it's deficiency may be related to infection rate, case fatality rate and clinical symptoms of COVID - 19. In view of this, the study starts with the potential mechanism of vitamin D in the prevention and treatment of COVID - 19, combined with current epidemiological research results and relevant clinical evidences on the relationship between vitamin D and COVID - 19, and synthesizes current progress in researches on the relationship between vitamin D and COVID - 19, to provide new thought for the prevention and treatment of COVID - 19.