Werther is an opera in four acts by Jules Massenet to a French libretto by Édouard Blau, Paul Milliet and Georges Hartmann. It is loosely based on Goethe's epistolary novel The Sorrows of Young Werther, which was based both on fact and on Goethe's own early life. Earlier examples of operas using the story were made by Kreutzer (1792) and Pucitta (1802).

Jules Émile Frédéric Massenet was a French composer of the Romantic era best known for his operas, of which he wrote more than thirty. The two most frequently staged are Manon (1884) and Werther (1892). He also composed oratorios, ballets, orchestral works, incidental music, piano pieces, songs and other music.