Rubem Fonseca (born May 11, 1925) is a Brazilian writer.

He was born in Juiz de Fora, in the state of Minas Gerais, but he has lived most of his life in Rio de Janeiro. In 1952, he started his career as a low-level cop and, later became a police commissioner, one of the highest ranks in the civil police of Brazil. Following the steps of American novelist Thomas Pynchon, a close friend of Fonseca, he refuses to give interviews and feels strongly about maintaining his privacy.