There are many sexually transmitted diseases, about 20 kinds of which have been found, mainly gonorrhea, syphilis, nongonococcal urethritis, AIDS, hepatitis B, hepatitis C and other diseases. 1. Gonorrhea: Neisseria gonorrhoeae causes purulent infections in the genitourinary tract, clinically manifested as urinary frequency, urgency and pain, etc., which can be transmitted through sexual intercourse. 2. Syphilis: due to syphilis spirochete infection, according to the different ways of transmission, it is divided into acquired syphilis and fetal syphilis. 3. Non-gonococcal urethritis: caused by infection by pathogens other than gonococcus, clinically manifested as painful urination and increased urethral discharge. 4. AIDS: mainly human immunodeficiency virus infection, clinically manifested as early infection can be asymptomatic, later mainly manifested as opportunistic infections, and is not easy to control, and prone to tumors. Transmission modes include sexual transmission, blood transmission, and mother-to-child transmission. 5. Hepatitis B and C can also be transmitted through sexual behavior. If symptoms of suspected sexually transmitted diseases appear, it is recommended to go to the hospital in time to avoid delay.