French composer best known for his operas, particularly Mignon, written in a light, melodious style.

Thomas attended the Paris Conservatory, concluding his studies by winning the Prix de Rome in 1832 for his cantata Hermann et Ketty. Upon his return from Rome in 1835 he launched himself on a career as an opera composer and began teaching at the conservatory in 1856.

After a series of pleasantly melodious works he produced his masterpiece and one of the most successful operas in history, Mignon (1866), which by 1894 had received more than 1,000 performances at the Opéra-Comique alone. This and his next opera, Hamlet (1868), brought him international fame, and in 1871 he became director of the Paris Conservatory.