Nicola Francesco Haym (6 July 1678 – 31 July 1729) was an Italian opera librettist, composer, theatre manager and performer, literary editor and numismatist. He is best remembered for adapting texts into libretti for the London operas of George Frideric Handel and Giovanni Bononcini. Libretti that he provided for Handel included those for Giulio Cesare, Ottone, Flavio, Tamerlano, Rodelinda, and several others; for Bononcini, he produced two, Calfurnia and Astianatte.