The article first defines the term of sport, says something about sport psychology, benefits of sport, emotional context of sport, and about possible psychosocial changes in children and young people brought by sport. Then comes the paragraph about violence. The concept of violence is defined and the difference between the terms "violence" and "abuse" between children and young people is explained. Furthermore, the paper briefly describes the notion of fair play and explains in more detail the occurrence of violence among children in sports, especially in football, one of the most popular sports, both in Croatia and in the world. The next paragraph is dealing with the role of a social worker in this area. At the very end of the paper, important facts are repeated, and importance of sport in the lives of children is emphasized. What is also emphasized is importance of preventing violence among children in sport, and importance of roles that parents and coaches should have in the lives of children, and the role which social workers might have.