José Carlos Fulgencio Pedro Regalado de la Riva-Agüero y Looz Corswarem (Brussels, Belgium, 25 May 1827 – Lima, Peru, 16 August 1881) was a Peruvian politician and diplomat.
He was the son of José de la Riva Agüero, Marquess of Montealegre de Aulestia, first President of Peru, and the Belgian princess Caroline-Arnoldine de Looz-Corswarem.
Member of the Civilista Party, was Finance Minister, Minister of Foreign Affairs and President of the Senate of the Republic of Peru.