The DSV Alvin is a manned deep-ocean research submersible owned by the United States Navy and operated by the Woods Hole Oceanographic Institution. Commissioned June 5, 1964, it remains in active operation today in worldwide oceanographic research. It is launched from the deep submergence support vessel Atlantis, also owned by the Navy and operated by WHOI.

Alvin was designed as a replacement for bathyscaphes and other less maneuverable oceanographic vehicles. It is a three-person vessel, carrying two scientists and one pilot on dives up to eight hours long and 4500 meters deep. It mounts two robotic arms and can be fitted with mission-specific sampling and experimental gear. It is named both for its proponent Allyn Vine and for the cartoon character "Alvin the Chipmunk."

In 2001, Alvin underwent an extensive overhaul to upgrade its motor controllers, computer systems, and other components.

See also: http://www.whoi.edu/marops/vehicles/alvin/index.html