Leopold Koželuch (Czech pronunciation: [ˈlɛopolt ˈkoʒɛlux], born Jan Antonín Koželuh, alternatively also Leopold Koželuh, Leopold Kotzeluch; 26 June 1747 – 7 May 1818) was a Czech composer and music teacher.
He was born in Velvary and moved to Prague to further his musical education, before moving again to Vienna in 1778, where he was based for the remainder of his career. In Vienna he achieved renown as a composer, pianist and teacher, and from 1792 until his death in 1818 he held royal appointments as Kammer Kapellmeister (music director) and Hofmusik Compositor (composer), as Wolfgang Amadeus Mozart's successor.
Koželuch's compositional output included sonatas and concertos for keyboard, the instrument in which he specialised, as well as chamber music, choral music and opera.
Koželuch left around 400 compositions. Among these there are about thirty symphonies, twenty-two piano concertos, including a concerto for piano four-hands, arguably one of the best examples of this rare genre, two clarinet concertos, twenty-four violin sonatas, sixty-three piano trios, six string quartets, two oratorios (one of which, Moisè in Egitto, has recently been produced and recorded), nine cantatas and various liturgical works. Among his music there are also operas and works for ballet, which—with the exception of one opera —have yet to be heard in recent years. Numerous arrangements by him of Scottish songs for the Edinburgh collector George Thomson were popular, and some of these have also been recorded.