William Alexander Barrett Free sheet music
- Born: 15th October 1834
- Died: 17th October 1891
- Birthplace: Hackney, Middlesex, England
William Alexander Barrett was an english writer and lecturer in music of the 'Morning Post' and other publications. He wrote monographs on the English Glee and Madrigal Writers. He also composed madrigals, anthems and an oratorio.