Ruy Alexandre Guerra Coelho Pereira (born August 22, 1931) is a Portuguese-Brazilian film director and screenwriter.

The tumultuous political landscape in 1970's Brazil forced Guerra to stop filming until 1976, when he directed A Queda.

While in Mozambique, Guerra shot many short films and helped the creation of the National Institute for Cinema.

He also directed the musical comedy A Ópera do Malandro (1985), based on Chico Buarque's free theatrical adaptation of Bertold Brecht's Threepenny Opera; the TV film Os Amores Difíceis, another adaptation of García Márquez; and Kuarup (1989).

[5] Guerra has appeared in many films as an actor; he is perhaps best known to international audiences for his performance as the doomed Pedro de Ursúa in Werner Herzog's Aguirre, the Wrath of God (1972).