Adolescence represents the period of maturation when young people transition from childhood to adulthood. It is the periphery when they are looking for their place in society, seeking their identity while at the same time responding to numerous demands from their environment. With many problems, sexual behavior is one of the main issues that adolescents want to explore. Due to insufficient information, lack of open communication in the family, and the belief that nothing can happen to them and to influence the media and society, adolescents are very early in their sexual relations, they often change partners, do not use protection during sexual intercourse, which can have destructive consequences for their health and the health of society. Sexually transmitted infections and diseases that are developing as a consequence of this are a major public health problem in the world and in us that disturb the quality of life of the individual but also of society at large. The most common sexually transmitted infections are chlamydia infections, gonorrhea, syphilis, human papilloma virus infection, herpes simplex virus infection, HIV, hepatitis, fungal infections and so on. It is clear that sexually transmitted infections can not be suppressed, but preventative measures can reduce their prevalence. In the prevention, special emphasis is placed on informing the young, acquainting with the consequences of unwanted sexual intercourse. It is necessary to raise awareness of the occurrence, enlargement and harmful effects of sexually transmitted diseases on the human body, but the destructive consequences of infected persons.