Robert Jemison Van de Graaff, (December 20, 1901 – January 16, 1967) was an American physicist and instrument maker, and professor of physics at Princeton University.
Robert Jemison Van de Graaff was born at the Jemison-Van de Graaff Mansion in Tuscaloosa, Alabama, from Dutch descent. In Tuscaloosa, he received his BS and Masters degrees from The University of Alabama where he was a member of The Castle Club (later became Mu Chapter of Theta Tau).
Van de Graaff was the designer of the Van de Graaff generator, a device which produces high voltages. In 1929, Van de Graaff developed his first generator with help from Nicholas Burke (producing 80,000 volts) at Princeton University; by 1931, he had constructed a much larger generator, capable of generating 7 million volts. He was a National Research Fellow, and from 1931 to 1934 a research associate at the Massachusetts Institute of Technology. He became an associate professor in 1934 (staying there until 1960). He was awarded the Elliott Cresson Medal in 1936.