Human immunodeficiency Virus (HIV) is mainly transmitted by sexual intercourses. History of STD’s and serological markers of STD’s are frequently encountered in HIV-infected patients. This is partly due to a common mode of transmission. However, it has been clearly demonstrated that ulcerative and non ulcerative STD’s are able to favour the sexual transmission of HIV. In addition, the HIV epidemic has a profound impact on clinical presentation of STD’s and justify specific therapeutical attitudes.