Marion Kirkland "Kirk" Fort Jr. (1921–1964) was an American mathematician, specializing in general topology.
Fort was born in 1921 in Spartanburg, South Carolina, where he graduated with an A.B.
in 1944 from the University of Virginia, where he also received his Ph.D. in 1948, advised by Gordon Thomas Whyburn.
In 1963 Fort became the first holder of the university's David C. Barrow Chair of Mathematics.
He died in 1964 during a leave of absence at the Institute for Defense Analyses in Princeton, New Jersey.