Manon Lescaut is an opera in four acts by Giacomo Puccini. The story is based on the 1731 novel L’histoire du chevalier des Grieux et de Manon Lescaut by the Abbé Prévost and should not be confused with Manon, an 1884 opera by Jules Massenet based on the same novel.

The libretto is in Italian, and was cobbled together by five librettists whom Puccini employed: Ruggero Leoncavallo, Marco Praga, Giuseppe Giacosa, Domenico Oliva and Luigi Illica. The publisher, Giulio Ricordi, and the composer himself also contributed to the libretto. So confused was the authorship of the libretto that no one was credited on the title page of the original score. However, it was Illica and Giacosa who completed the libretto and went on to contribute the libretti to Puccini's next three – and most successful – works, La Bohème, Tosca and Madama Butterfly.

Puccini's publisher, Ricordi, had been against any project based on Prévost's story because Jules Massenet had already made it into a successful opera, Manon, in 1884. While Puccini and Ricordi may not have known it, the French composer Daniel Auber had also already written an opera on the same subject with the title Manon Lescaut, in 1856.

Despite all the warnings, Puccini proceeded. "Manon is a heroine I believe in and therefore she cannot fail to win the hearts of the public. Why shouldn’t there be two operas about Manon? A woman like Manon can have more than one lover." He added, "Massenet feels it as a Frenchman, with powder and minuets. I shall feel it as an Italian, with a desperate passion."