Vladimir Aleksandrovich Fock (or Fok; Russian: Влади́мир Алекса́ндрович Фок) (December 22, 1898 – December 27, 1974) was a Soviet physicist, who did foundational work on quantum mechanics and quantum electrodynamics.

His primary scientific contribution lies in the development of quantum physics and the theory of gravitation, although he also contributed significantly to the fields of mechanics, theoretical optics, physics of continuous media.

Fock made significant contributions to general relativity theory, specifically for the many-body problems.

Fock criticised on scientific grounds both Einstein's general principle of relativity, as being devoid of physical substance, and the equivalence principle, as interpreted as the equivalence of gravitation and acceleration, as having only a local validity.

Historians of science, such as Loren Graham, see Fock as a representative and proponent of Einstein's theory of relativity within the Soviet world.