Francis Thomas Farrell (born November 14, 1941, in Ohio, United States) is an American mathematician who has made contributions in the area of topology and differential geometry.

His Ph.D. advisor was Wu-Chung Hsiang, and his doctoral thesis title was "The Obstruction to Fibering a Manifold over a Circle".

In 1970, Farrell was invited to give a 50-minute address at the International Congress of Mathematicians about his thesis in Nice, France.

[3][4] In 1990, for their joint work on Rigidity in Geometry and Topology, his co-author Lowell E. Jones was invited to give a 45-minute address at the International Congress of Mathematicians in Kyoto, Japan.

[7] In his thesis, Farrell solved the problem of determining when a manifold (of dimension greater than 5) can fiber over a circle.