Luigi Macchi (3 March 1832, in Viterbo – 29 March 1907, in Rome) was an Italian Catholic nobleman and a Cardinal.
He was a nephew of Cardinal Vincenzo Macchi. In 1859, he was ordained a priest. In 1860, he was referendary of the Tribunal of the Apostolic Signature of Grace. Pope Leo XIII created him a cardinal in the consistory of 11 February 1889. As protodeacon since 1899, Cardinal Macchi announced the election of cardinal Giuseppe Sarto at the end of the conclave of 1903 and crowned him on 9 August 1903. Four years later, Cardinal Macchi died after an illness at the age of 75.