William Henry Barbour, Jr. (born 1941) is a United States federal judge.
Barbour was born in Yazoo City, Mississippi, and attended New York University School of Law. He received a B.A. from Princeton University in 1963, and a J.D. from the University of Mississippi School of Law in 1966. He was in private practice of law in Yazoo City from 1966 to 1983, and was also a youth counselor for the Yazoo City Court from 1971 to 1982.
Barbour was a federal judge on the United States District Court for the Southern District of Mississippi. Barbour was nominated by President Ronald Reagan on March 15, 1983, to a seat vacated by William Harold Cox. He was confirmed by the United States Senate on April 21, 1983, and received his commission on April 25, 1983. He served as chief judge from 1989 to 1996, and assumed senior status on February 4, 2006.