Human immunodeficiency virus, or HIV, antibody negativity means that no antibodies against HIV have been detected in the blood. After the human body is infected with HIV, the body’s immune system will produce antibodies against HIV, and by detecting these antibodies, it can be indirectly deduced whether or not the body is infected with HIV. Therefore, there are two scenarios if the test is negative for antibodies. One is that you have not been infected with HIV, so you will not have antibodies against HIV, and a negative test proves that you are healthy and not infected. The other case is that the person has been infected with HIV, but not for a long time, and is still in the window period of antibody production, and there are not enough antibodies in the blood to be detected, so the test is negative for the time being. The window period is usually about 4-6 weeks and can be up to three months. If the test is negative, but there is a possibility of high-risk behavior and infection, the test can be repeated in about three months, and if it is still negative, HIV infection can be ruled out.