Ulrich Leyendecker (29 January 1946 — 29 November 2018) was a German composer of classical music. His output consisted mainly of symphonies, concertos, chamber and instrumental music.
Leyendecker studied composition with Ingo Schmitt (1962–1965) and Rudolf Petzold (1965–1970), and piano with Günter Ludwig. In 1971 he became a lecturer at the Hamburg Academy for Music and Performing Arts, and in 1976 he was appointed Professor of Composition and Theory at the Hamburg Music and Theatre Hochschule. In 1994, he became Professor of Composition at the State Hochschule for Music and the Performing Arts of Heidelberg-Mannheim.
Leyendecker's music, although not serial, is largely atonal, but often with subtle hints of tonality. He employed regular time signatures in his pieces, but it sometimes does not sound that way, for he utilized carefully calculated and complex rhythms. His music often contains novel sonic architectures, while still managing to express powerful emotions directly to the listener. He often employed classical abstract forms such as the symphony and concerto form while avoiding operas and ballets.