Quantum theory may refer to:
Science Quantum mechanics, a major field of physics Old quantum theory, predating modern quantum mechanics Quantum field theory, an area of quantum mechanics that includes: Quantum electrodynamics Quantum chromodynamics Electroweak interaction Quantum gravity, a field of theoretical physics Quantum optics Quantum chemistry Quantum information Quantum Theory: Concepts and Methods, a 1993 book by Asher Peres
Arts and other media Quantum Theory (video game), a 2010 video game "Quantum Theory", a song on the Jarvis Cocker album Jarvis