Leonard Cecil Feldman (born New York City, 8 June 1939) is an American materials physicist.
He then joined AT&T Bell Laboratories, working on semiconductor materials physics.
In 1996 he assumed the position of Stevenson Professor of Physics at Vanderbilt University and Distinguished Visiting Scientist at Oak Ridge National Laboratory.
His current interest concerns the effect of ion beam on nanostructures and organic materials.
He was named Fellow of the Institute of Electrical and Electronics Engineers (IEEE) in 2016 "for contributions to semiconductor-dielectric interfaces for MOS technologies".