Haircutting is not contagious because hair does not have blood vessels and other corresponding tissues, so HIV cannot be transmitted through hair. The main ways of HIV transmission are blood transmission, sexual transmission and mother-to-child transmission. If the person whose hair is being cut is injured by the hair-cutting instrument in the process of hair-cutting, and if the hair-cutting instrument contains the blood of an AIDS patient, there is a possibility that HIV can be transmitted through his blood, but of course the chance is very low, and there has not been any report of anyone getting infected by HIV because of hair-cutting, so there is no need to worry too much about it. So there is no need to worry too much. If you want to prevent HIV infection, you should be clean in your daily life, keep a regular sexual partner, and avoid invasive operations such as tooth extraction, eyebrow tattooing, tattooing, etc. in irregular places.