Stanley S. Ballard (1908–1998) was an American physicist, specializing in optics. He was president of the Optical Society of America in 1963 and of the American Association of Physics Teachers during 1968–69. In 1986 he was awarded the Oersted Medal. During World War II, Ballard served as a Commander in the United States Navy. From 1956 to 1959 he was the President of the International Commission for Optics.
Ballard obtained his Ph.D and M.Sc. in physics from the University of California, Berkeley, and his undergraduate degree from Pomona College. He served on the faculties of several physics departments, including as chairman at Tufts University and the University of Florida. He coauthored the books, Polarized Light (with William A. Shurcliff) and Physics Principles (with Edgar P. Slack and Erich Hausmann).