This article is an attempt to understand violence in adolescence following Freud and Lacan's work who have linked narcissism and aggression. At a point when Thanatos does not submit to Eros, meaning aggression is misused, violence emerges. Having a closer look at the violence of youth highlights especially three themes: the destructive violence that evolve by itself, sexual violence that is committed in group, and the formation of groups with violent tendencies on the basis of discrimination. (ed.)