Palacete de São Bento, formally the Official Residence of the Prime Minister, is a late 19th-century mansion that presently serves as the official residence of the prime minister of Portugal. It is located in the Lisbon civil parish of Estrela, within the grounds of São Bento Palace, the seat of the Portuguese parliament.

The São Bento Palace in Lisbon is the seat of the Assembly of the Portuguese Republic, the parliament of Portugal. Originally constructed in 1598, São Bento has served as the seat of Portugal's parliament since 1834, when the former monastery of the Benedictine Order was dissolved after the Liberal Wars. During the Portuguese constitutional monarchy, the palace served as the seat of the Cortes Gerais, the traditional parliaments of Portugal, until 1910.