António Mendes Belo (18 June 1842 – 5 August 1929) was a Portuguese prelate of the Catholic Church, who served as Patriarch of Lisbon from 1907 until his death. He was made a Cardinal of the Roman Catholic Church in 1911, though his elevation to that rank was not announced until 1914. He was Auxiliary Bishop of Lisbon from 1884 to 1888 and Archbishop of Faro from 1888 to 1906.