Lloyd Ultan (New York City, June 12, 1929 – October 26, 1998) was an American composer of contemporary classical music.
In 1971, he founded, and, from 1971 to 1974, served as Director of the Composer's Residency Program at Wolf Trap Farm Park in Vienna, Virginia.
His works have been performed by the Tokyo String Quartet, the Pro Arte String Quartet, the Minnesota Orchestra, the St. Paul Chamber Orchestra, the Boston Symphony, William Blount, Alexander Braginsky, Young Nam Kim, Tanya Remenikova, and Thomas Murray.
He has written numerous articles and a book, Music Theory: Compositional Problems and Practices in the Middle Ages and Renaissance (with an accompanying workbook/anthology).
Ultan's notable students include Edie Hill and Scott L. Miller.