Infante D. Afonso of Braganza, Duke of Porto (Portuguese pronunciation: [ɐˈfõsu]; 31 July 1865 in Palace of Ajuda, Lisbon – 21 February 1920 in Naples, Italy) was a Portuguese Infante of the House of Braganza, the son of King Luis I of Portugal and his wife, Maria Pia of Savoy. From 1908 to the abolition of the Portuguese monarchy in 1910 he was the Prince Royal of Portugal as heir presumptive to his nephew, King Manuel II.