Forum theater is part of technique that is called theater of the oppressed. Theatre of the Oppressed is developed over the past thirty years, by the Brazilian director Augusto Boal. This system of theater exercises, games and techniques aims to develop the oppressed people (all of them who are fully or partially deprived of dialogue) theatrical language as a basic human language that can communicate with other social subjects and to express their will and their wishes. It is an interactive theater where the audience, with the mediation role of joker actively by questions, suggestions and role-play - participate in solving some of the social, seemingly unsolvable problems. At the same time, it does not require one, right or perfect solution, but the aim is to look at the story from multiple perspectives that can open up more opportunities. Acting inside the safe theater space, viewers-actors have the opportunity to observe themself, to learn by experience and to be prepared to act in real life. Therefore, the subject of this paper is to point out the role of theater in society, and above all, it refers to engaged theater like Theater of the Oppressed, which becomes a space in which certain social problems such as prejudice, stereotyping and discrimination can be presented and viewed freely and critically. This paper describes the atmosphere and the formation of the basic settings of Theater of the Oppressed which are found in the basic idea of dialogue, open space of action and reflect that action to persons and communities that are exposed to oppression. Furthermore, this paper shows the application of techniques Forum Theatre of the Oppressed through various social groups, and points out its advantages in the prevention of discrimination and educational power in the understanding of social reality.