Andrzej Ehrenfeucht (Polish: [ˈand.ʐɛj ˈɛrɛnfɔjxt], born 8 August 1932) is a Polish-American mathematician and computer scientist.
Andrzej Ehrenfeucht formulated the Ehrenfeucht–Fraïssé game, using the back-and-forth method given in Roland Fraïssé's PhD thesis.
In 1971 Ehrenfeucht was a founding member of the Department of Computer Science at the University of Colorado at Boulder.
Two of Ehrenfeucht's students, Eugene Myers and David Haussler, contributed to the sequencing of the human genome.
They, with Harold Gabow, Ross McConnell, and Grzegorz Rozenberg, spoke at a 2012 University of Colorado two-day symposium honoring Ehrenfeucht's 80th birthday.