John Andrew Dillon Jr. (1923 – February 22, 2005) was an American physicist, administrator, professor at the University of Louisville, and founder and first director of the Systems Science Institute at the University of Louisville.
John Dillon served in the U.S. Army Air Forces during the course of the war, where he worked on the development of Radar systems and guided missiles.
In 1966 he went to the University of Louisville as dean of the graduate school, where he taught physics until he retired in 1986.
He also was dean of graduate studies until 1990 at Spalding University, where he had previously been provost.
In 1986, he was awarded the title of Distinguished Teaching Professor and became an associate in the department of community health of the school of medicine.