1, high-risk sex is the act of exchanging bodily fluids with others, that is, someone else’s bodily fluids into their body, or their bodily fluids into someone else’s body , professionally speaking, it is unsafe sexual intercourse without any protection. According to the transmission route of HIV, the behavior that can easily cause HIV transmission is called high-risk behavior. 2, specific high-risk behavior or high-risk sexual behavior are as follows: (1) through the sexual route of high-risk sexual behavior are: really counted as high-risk sexual behavior is not to take any protective measures of sex, such as unprotected intercourse, multiple sexual partners, etc.. (2) High-risk behaviors through the blood route include: sharing syringes with others to inject drugs intravenously is high-risk behavior (if you have disposable syringes there is no possibility of HIV infection). Sharing needles for intravenous drug use; sharing syringes or other devices that can pierce the skin; using untested blood or blood products. (3) High-risk behaviors through the mother-to-child route include: pregnancy and childbirth in HIV-positive women; breastfeeding in HIV-positive mothers may cause HIV infection in their children. (4) Other possible ways to cause blood transmission: such as for tattoos, haircuts, pierced ears and eyes, beauty, pedicures and other knives are not sterilized lacerations; sharing with others shaving knife, toothbrush; trauma and fights caused by bleeding; rescue of the wounded, the rescuer’s broken skin contact with the blood of the wounded, and confirm that the other party has AIDS infection. 3.It is possible to transmit AIDS from oral sex, but the probability is low. Only in the case of high-risk behavior or high-risk sexual behavior is there a possibility of HIV infection. Other than that, other behaviors are unlikely to infect AIDS.