Quantum hydrodynamics is the study of superfluidity. Some of the main subjects in quantum hydrodynamics are quantum turbulence, quantized vortices, first second and third sound; and quantum solvents.

The most common studies are in liquid helium (He-3 and He-4), and of the interior of neutron stars. Many famous scientists have worked in quantum hydrodynamics such as Richard Feynman, Lev Landau, and Pyotr L. Kapitsa.