Joseph Elvin "J. Ebb" Duncan (February 18, 1909 – January 19, 1980) was an American politician from the U.S. state of Georgia.
Duncan was also a member of numerous community organizations and served on the board of directors for several local businesses.
He was instrumental in bringing educational television to Georgia, making the University of West Georgia into a four-year institution, and supporting the creation of the university's modern campus.
Duncan's activities in the Georgia Senate, including legislation on the World Congress Center, education, mental health, banks and banking, and the disabled.
He also led the state congressional committee on the Georgia World Congress Center and its subsequent development into a world-class exhibition location.