Blisters on the scrotum may be a sign of infection in the body, a symptom of some diseases such as genital herpes and warts. 1. Genital herpes: Genital herpes is a sexually transmitted disease infected by the herpes simplex virus, which is easily repeated and difficult to cure. Different types of genital herpes have different manifestations, and the main clinical symptoms are blisters and vesicles with pain and itching around the genitals, as well as headache and fever. 2. Warts: Warts is a sexually transmitted disease caused by human papilloma virus infection, mainly through sexual transmission. Typical clinical symptoms include a foreign body sensation around the genitals, pain and itching, single or multiple light red particles, and localized blisters. When patients experience discomfort, they should go to the hospital immediately.