Faustina Bordoni (30 March 1697 – 4 November 1781) was an Italian mezzo-soprano.
She was born in Venice and brought up under the protection of the aristocratic brother composers Alessandro and Benedetto Marcello. Her singing teacher was another composer, Michelangelo Gasparini. For many years in the service of the Elector Palatine, she made her operatic debut at Venice in 1716 in Carlo Francesco Pollarolo's Ariodante, singing in her home city until 1725 in operas by Albinoni, the Gasparini brothers, Giacomelli, Leonardo Leo, Giuseppe Maria Orlandini, the Pollarolos, father and son, and Leonardo Vinci, amongst others. In 1718 and 1719 in Venice she sang alongside Francesca Cuzzoni, later to become her great rival. During this period she also performed several times at Reggio nell'Emilia, Naples and Parma, and at least once in Milan, Modena and Florence. After her German début in 1723, singing in Pietro Torri's Griselda at Munich, she was a great favourite north of the Alps during the 1720s, also enjoying great success in Vienna (1725–26). Her nickname was the "new siren", and she was commonly known simply as "Faustina".
Her London début, as Rossane in Handel's Alessandro, took place on 5 May 1726, alongside Senesino and Cuzzoni. During the next two seasons she created four more Handel roles: Alceste in Admeto and Pulcheria in Riccardo Primo (both 1727), and Emira in Siroe and Elisa in Tolomeo (1728). She also sang in a revival of Radamisto, and in operas by Ariosti and Giovanni Bononcini. In a performance of the latter's Astianatte on 6 June 1727, a riot broke out in the audience between her followers and those of her 'rival' Cuzzoni in the King's Theatre, Haymarket, in front of Caroline, Princess of Wales. This furore seized the public imagination and a great deal of journalistic exaggeration – the pamphleteer John Arbuthnot published "The DEVIL to pay at St. JAMES's: Or A full and true ACCOUNT of a most horrid and bloody BATTLE between Madam FAUSTINA and Madam CUZZONI", in which he lambasted the two ladies: "TWO of a Trade seldom or ever agree … But who would have thought the Infection should reach the Hay-market and inspire Two Singing Ladies to pull each other's Coiffs, to the no small Disquiet of the Directors, who (God help them) have enough to do to keep Peace and Quietness between them. … I shall not determine who is the Aggressor, but take the surer Side, and wisely pronounce them both in Fault; for it is certainly an apparent Shame that two such well bred Ladies should call Bitch and Whore, should scold and fight like any Billingsgates." Recent research has shown, however, that it was the singers' supporters who were behaving badly, rather than the singers themselves, who had worked together before in Italy and continued to work together for the Royal Academy until the directors were forced to dissolve it in 1728 owing to mounting debts.