Al Cisneros is an American musician. He is the lead singer and bassist for stoner rock/doom metal bands Sleep and Om. He also was a member of Shrinebuilder and Asbestosdeath and has put out nine releases as a solo artist.

Sleep is an American stoner/doom metal band from San Jose, California. Guitarist Matt Pike and bassist and vocalist Al Cisneros have been the only constant members throughout the band's history. Critic Eduardo Rivadavia describes them as "perhaps the ultimate stoner rock band" and notes they exerted a strong influence on metal in the 1990s.