It was recommended to use nCoV-IgM /IgG to specifically detect the antibodies of the novel coronavirus (2019-ncov) in the blood, to exclude fever cases caused by other viruses, or to diagnose the 2019-nCoV infection. It is a very effective method of the covid-19 antibody test. After the human body was infected with the novel coronavirus, the human body would produce corresponding antibodies, IgM comes first. When IgM production declines, IgG production is accelerated to cope with the invasion of pathogens.