Peter Pulay (born September 20, 1941, in Veszprém, Hungary) is a theoretical chemist.
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.
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.