The Grumman G-65 Tadpole was an American prototype light amphibian designed and built by Grumman. Only one was built and it did not enter production. It was later developed into a family of amphibious aircraft by David Thurston.
Part of a project by Grumman to find types to produce once the Second World War had finished, the G-65 Tadpole was designed by a team under the direction of Hank Kurt. The Tadpole was a two or three-seat shoulder-wing cantilever monoplane with retractable tricycle landing gear. It was powered by a 125 hp (93 kW) Continental C125 engine above the rear fuselage driving a pusher propeller. Kurt first flew the Tadpole on 7 December 1944. Although not developed by Grumman, one of the design team, David Thurston, later developed the design into a family of amphibians including the Colonial Skimmer and Lake Buccaneer.