John Hart Ely (December 3, 1938 – October 25, 2003) was an American legal scholar known for his studies of constitutional law.
He was a professor of law at Yale University from 1968 to 1973, at Harvard University from 1973 to 1982, then at Stanford University from 1982 to 1996, where he served as dean of the Stanford Law School from 1982 to 1987.
Ely was one of the most widely cited legal scholars in United States history, ranking just after Richard Posner, Ronald Dworkin, and Oliver Wendell Holmes, Jr., according to a 2000 study in the University of Chicago's Journal of Legal Studies.