The purified confirmed HIV protein antigen was cleaved, and then separated by SDS-PAGE according to molecular weight, then transferred to nitrocellulose membrane, and stored in a dry test tube at 4 °C. The plain film reacts with the sample to be tested to make it fully contact. If the sample contains HIV antibody, it will bind to the antigen zone on the membrane strip, and then add the enzyme-labeled anti-human IgG antibody, and then react with the substrate to develop color, and then different zones visible to the naked eye can be formed.