He was born in Somerville, Massachusetts.
Clement is widely considered to be a leader of the subgenre hard science fiction.
His educational background includes a B.S. in astronomy from Harvard in 1943, M. Ed. (Boston University 1946), and M.S. in chemistry (Simmons College 1963). During the World War II he was a pilot and copilot of the B-24 Liberator and flew 35 combat missions over Europe with 8th Air Force. He served in the Army Air Corps Reserve, and retired with the rank of colonel. He taught chemistry for many years at Milton Academy in Milton, Massachusetts.
Clement received the 1998 recognition as a Grand Master by the Science Fiction and Fantasy Writers of America (SFWA). In 1996 he retroactively received a 1946 Hugo Award for his short story "Uncommon Sense".
His best-known novel, Mission of Gravity, is the account of an overland expedition across the superjovian planet Mesklin to recover a crashed scientific probe. The natives of Mesklin are centipede-like intelligent beings about a meter in length. Various episodes hinge on the fact that Mesklin's fast rotational speed causes it to be considerably deformed from the spherical, and its effective surface gravity to vary from approximately 3 G at the equator to approximately 700 G at the poles.
Clement's article "Whirligig World" describes his approach to writing a science fiction story:
Clement was a frequent guest at science fiction conventions, especially in the eastern United States, where he usually presented talks and slide shows about writing and astronomy.