AIDS is a contagious disease and oral sex carries the risk of spreading AIDS. AIDS is caused by infection with the HIV virus. After infection, patients will suffer from varying degrees of immune deficiency, and if left untreated, it may induce a variety of serious infections, and in severe cases, malignant tumors may result in death. HIV is contagious, and the ways of transmission of HIV include unprotected sex, intravenous drug use, mother-to-child transmission, and transmission through blood. Oral sex is the process of touching the genitals with the mouth or throat during sexual intercourse, as the vaginal secretions and semen of AIDS patients will contain HIV. If the person concerned has a broken or ulcerated mouth, HIV will enter the body through the broken mucous membrane, leading to the spread of AIDS. Oral sex may transmit HIV, and it is recommended that people with HIV seek prompt medical attention and avoid risky sexual behavior to minimize the spread of HIV.