Marshall Nicholas Rosenbluth (5 February 1927 – 28 September 2003) was an American plasma physicist and member of the National Academy of Sciences. In 1997 he was awarded the National Medal of Science for discoveries in controlled thermonuclear fusion, contributions to plasma physics, and work in computational statistical mechanics. He was also a recipient of the E.O. Lawrence Prize (1964), the Albert Einstein Award (1967), the James Clerk Maxwell Prize in Plasma Physics (1976), the Enrico Fermi Award (1985), and the Hannes Alfvén Prize (2002).