Guilherme Taucci Monteiro (July 5, 2001 - March 13, 2019) was a Brazilian who, together with his friend, Luiz Henrique de Castro, killed five students and two school staff members at the Professor Raul Brasil State School in the Brazilian municipality of Suzano, São Paulo State. The pair also killed Monteiro's uncle. After the shooting, Taucci killed Luiz and committed suicide.