Niccolò Fortiguerra (also spelled Forteguerri) (1419 – 21 December 1473) was an Italian papal legate, military commander, and Cardinal.
Born at Pistoia, he was related to Pope Pius II and is counted as a cardinal-nephew. He had a doctorate in utroque iure from the University of Siena.
He became bishop of Teano in 1458, and Cardinal in 1460. In 1462 he campaigned in the Papal States against Sigismondo Pandolfo Malatesta, taking Fano. Later, in 1465, he defeated Deifobo d'Anguillara in battle.
He died at Viterbo in 1473.