Infanta Mafalda of Portugal (Portuguese pronunciation: [mɐˈfaɫdɐ]) was a Portuguese infanta (princess), later Queen consort of Castile for a brief period. She was the second youngest daughter of King Sancho I of Portugal and Dulce of Aragon. She was born c. 1190. In 1215, Mafalda married Henry I of Castile. As he was very young, the marriage was not consummated, and it was dissolved in 1216. After that she became a nun in Arouca and died in Rio Tinto (Amarante) on May 1, 1256. On June 27, 1793 she was beatified.