Jean-Baptiste Rey (18 December 1734 – 15 July 1810) was a French conductor and composer. Rey was born at Lauzerte. He remains the longest-serving conductor of the Paris Opera; his tenure spans from the last years of the monarchy to Napoleon's Empire (1776–1810). As such, he conducted most performances of masterpieces by Gluck, Piccini, Sacchini, Salieri, Gretry, Méhul, Haydn, Mozart, Spontini, etc., many of whom he cooperated with closely. He was the author of an opera, Apollon et Coronis (1781) and several other pieces and arrangements. Rey also wrote the third act of Sacchini's Arvire et Évélina (1788).