Jacques-François-Fromental-Élie Halévy, usually known as Fromental Halévy (French: [fʁɔmɑ̃tal alevi]; 27 May 1799 – 17 March 1862), was a French opera composer, widely regarded in his lifetime as one of the central figures of 19th-century French music.

A student of Luigi Cherubini, he achieved his first major triumph with La Juive (1835), a cornerstone of the grand opéra repertoire, and which Gustav Mahler considered one of the greatest operas ever written. The 368th performance of La Juive inaugurated the new Paris opera house, the Palais Garnier, in 1875. Halévy's bust stands on the façade, with the inscription "Poésie lyrique" above it.

During the following two decades, Halévy became a leading presence on the Parisian stage, contributing more than 30 operas including grand opéra, opéra-comique, and opéra-lyrique.

Celebrated for uniting melodic invention with learned craftsmanship, Halévy was considered the leader of the French school; the greatest French musician of the modern dramatic school; and (with Daniel Auber) the most important French composer of serious opera since Jean-Philippe Rameau.

Many of his works were mainstays of the Opéra and Opéra-Comique for decades. L'Eclair (1835) was performed more than 200 times until 1899; La Reine de Chypre (1841) 152 times by 1879; Les Mousquetaires de la Reine (1846) 200 times by 1865; and Le Val d'Andorre, his second-most popular work after La Juive, 334 times.

Other notable successes included Le Dilettante d'Avignon (1829): 119 performances in Paris; La Tentation (1832): 102 performances; La Fée aux Roses (1849): 100 performances; and Jaguarita l'Indienne (1855), the Théâtre-Lyrique's longest running success to that point, 124 performances.

Despite much acclaim, Halévy's reputation waned after his death. By the 20th century, only La Juive remained in the repertoire.

Halévy's works have begun to re-emerge: La Reine de Chypre was revived in concert by the Palazzetto Bru Zane and awarded Gramophone’s Opera Recording of the Year (2018). Other modern revivals include Charles VI (1843) in Compiègne in 2005; Clari (1828) in Zurich, 2008, with Cecilia Bartoli; La Magicienne (1858) in Montpellier, 2011; Le Dilettante d'Avignon in Avignon, 2014; L'Éclair in Geneva, and La Tempesta in Wexford, both 2022.