Alessandro Mattei (20 February 1744, Rome – 20 April 1820) was an Italian Cardinal, and a significant figure in papal diplomacy of the Napoleonic period.

[1] From 1817 to his death he was archpriest of St Peter's Basilica.

Cardinal Bernardino Giraud consecrated Mattei to the episcopacy on 23 February 1777.

Having himself consecrated Pietro Francesco Galleffi to the episcopacy, Cardinal Mattei is in the episcopal lineage of Pope Francis.

This article about an Italian Catholic cardinal is a stub.