Gonorrhea: It is the most common sexually transmitted disease, infected by gonococcus, mainly transmitted directly by sexual contact, but may also be transmitted through other media, such as gonococcal contaminated towels, bedding, etc. Because of the short incubation period of about 2~5 days in men, according to the clinical manifestations (lyngeal urethritis), laboratory tests including smear staining of urethral secretions to find gram-negative diplococci is the most common detection method, and gonococci can be isolated and cultured in asymptomatic people. Chinese Academy of Traditional Chinese Medicine Xiyuan Hospital, Department of Men’s Gao Qing and mycoplasma, chlamydia: increases with the number of sexual partners, there are 30-40% of people without any symptoms present, the examination is mainly chlamydia culture, mycoplasma solium culture. The examination includes pathological examination, white acetate test. Syphilis: Syphilis is caused by the pale spirochete, which can invade all systemic organs, according to whether the infection is more than 2 years, can be divided into early syphilis and late syphilis, in addition to latent syphilis. Early syphilis is contagious, late syphilis is less contagious, untreated patients are most contagious within 1 year of infection, the disease period of more than 4 years is very little contagious. Stage I syphilis is mainly a hard chancre, which is a painless inflammatory reaction at the site of syphilis spirochete invasion, without systemic symptoms and fever. The incubation period is 1-8 weeks, with an average of 2-4 weeks. AIDS: HIV infection is a sexually transmitted disease caused by immune deficiency, a virus that can live in human blood and attack the body’s immune system. Common transmission routes include sexual transmission (blood, semen, vaginal secretions, etc.) and intravenous drug use. The incubation period of HIV is usually 2-10 years. Patients have no clinical symptoms during the incubation period, but it is not a quiescent or safe period. HIV is quite weak in the environment outside the human body and dies quickly if exposed to air, so it will not be spread by daily contact. In short, after unclean sex, you need to seek medical attention according to the symptoms and have the relevant examination by the doctor.