AIDS is an infectious disease. There are three elements in the occurrence of infectious disease: infectious source, transmission route and susceptible population. To control the source of infection, the three main aspects are as follows: First, to control the source of infection, the source of AIDS infection is HIV-infected people and AIDS patients. For humanitarian reasons, it is impossible to completely isolate the infected people and restrict their freedom, but early antiviral treatment can reduce the possibility of transmission to others. Second, the protection of vulnerable people, there is no AIDS vaccine, but before and after exposure to take antiviral drugs, can reduce the possibility of being infected. Third, the most important way to control HIV infection is to cut off the transmission channels, which are mainly sexual transmission, blood transmission and vertical transmission from mother to child, so all the current methods are centered on these three aspects. First, cleanliness, avoid sexual promiscuity, must avoid unclean sexual life. Secondly, use condoms correctly to reduce the risk of AIDS and STD. Do not transfuse blood of unknown origin, and use regular and qualified blood products. No intravenous drug use, no sharing of needles, no sharing of unsterilized medical devices. Lastly, interrupting vertical transmission from mother to child means taking antiviral drugs as early as possible for HIV-positive pregnant women and prophylactic drugs for 4-6 weeks after the birth of a newborn under the guidance of a doctor.