William Henry Barth (December 13, 1942, New York City – July 14, 2000, Amsterdam, Netherlands) was an American blues guitarist who, along with John Fahey and Henry Vestine, located 1930s blues great Skip James in a hospital in Tunica, Mississippi in 1964.
In the late 1960s Barth was a founding member of the band The Insect Trust.
Barth co-founded the Memphis Country Blues Society, a non-profit organization dedicated to the preservation and promotion of the Delta blues.
With the Country Blues Society, Bill produced five festivals between 1966 and 1970 featuring artists such as Furry Lewis, Gus Cannon, Bukka White, Sleepy John Estes, Yank Rachell and Fred McDowell.