Peter Pulay (born September 20, 1941, in Veszprém, Hungary) is a theoretical chemist. He is the Roger B. Bost Distinguished Professor of Chemistry in the Department of Chemistry and Biochemistry at the University of Arkansas, United States.
One of his most important contributions is the introduction of the gradient method in quantum chemistry. This allows the prediction of the geometric structure of a molecule using computational chemical programs to be almost routine. He is the main author of the PQS computational chemistry program.
His work was cited in the official background material for the 1998 Nobel Prize in chemistry.
Among many honors, he was made a Foreign Member of the Hungarian Academy of Sciences in 1993. He is a member of the International Academy of Quantum Molecular Science.