It is usually unlikely that a 9-week negative HIV test will turn positive, but regular monitoring is still required. AIDS, also known as Human Acquired Immunodeficiency Syndrome, is a systemic disease caused by infection of the body with the Human Immunodeficiency Virus (HIV). Sexual transmission, blood transmission and mother-to-child transmission are the main modes of transmission, the most common being transmission through unclean sex. Having multiple sexual partners or having unclean sex increases the risk of HIV infection. It is recommended to test for HIV infection in a timely manner after having high-risk sexual behavior. At the current stage, the window period for HIV testing is about 6 weeks, so when the test is more than 6 weeks old and the test result is negative, it generally means that HIV infection is less likely to change from negative to positive. However, the longest window period found for HIV antibody testing is 6 months, therefore, if the test is for HIV antibody, 9 weeks of negative HIV testing should not be taken lightly, and it is recommended to continue to improve the HIV antibody test 3 months and 6 months after the history of high-risk exposure. In summary, HIV 9 weeks has exceeded the current window period of HIV testing, so the test result is negative, suggesting that the possibility of negative to positive is low, do not need to be too nervous. If the test result is HIV antibody, continue to improve the HIV antibody test at 3 months and 6 months after the history of high-risk exposure.