Bernard Morris Dwork (May 27, 1923 – May 9, 1998) was an American mathematician, known for his application of p-adic analysis to local zeta functions, and in particular for a proof of the first part of the Weil conjectures: the rationality of the zeta-function of a variety over a finite field. For this proof he received, together with Kenkichi Iwasawa, the Cole Prize in 1962. The general theme of Dwork's research was p-adic cohomology and p-adic differential equations.