Jan Saxl (5 June 1948 – 2 May 2020) was a Czech-British mathematician, and a professor at the University of Cambridge.

Liebeck, Saxl and Praeger gave a relatively simple and self-contained proof of the O'Nan–Scott theorem.

[5] It had long been known that every maximal subgroup of a symmetric group or alternating group was intransitive, imprimitive, or primitive, and the same authors in 1988 gave a partial description of which primitive subgroups could occur.

[6][7] Saxl was married to Cambridge mathematician Ruth M. Williams and they had one daughter, Miriam.

[1] A three-day conference in the joint honor of Saxl and Martin Liebeck was held at the University of Cambridge in July 2015.