Harry Kesten (November 19, 1931 – March 29, 2019) was a Jewish American mathematician best known for his work in probability, most notably on random walks on groups and graphs, random matrices, branching processes, and percolation theory. Surviving the Holocaust, Kesten initially studied chemistry, and later theoretical physics and mathematics, at the University of Amsterdam. He moved to the United States in 1956 and received his PhD in Mathematics in 1958 at Cornell University under the supervision of Mark Kac. He was an instructor at Princeton University and the Hebrew University before returning to Cornell in 1961.

Kesten died on March 29, 2019, in Ithaca at the age of 87.