The Roman Catholic Diocese of Osasco () is a diocese located in the city of Osasco in the ecclesiastical province of São Paulo in Brazil.

History 15 March 1989: Established as Diocese of Osasco from the Metropolitan Archdiocese of São Paulo

Leadership Bishops of Osasco (Roman rite) Bishop João Bosco Barbosa de Sousa (2014.04.16 - today) Bishop Ercílio Turco (2002.04.24 – 2014.4.16) Bishop Francisco Manuel Vieira (1989.03.15 – 2002.04.24)

References GCatholic.org Catholic Hierarchy Diocese website (Portuguese)