Operation HIGHJUMP, officially titled The United States Navy Antarctic Developments Program, 1946–1947,, was a United States Navy (USN) operation to establish the Antarctic research base Little America IV. The operation was organized by Rear Admiral Richard E. Byrd, Jr., USN, Officer in Charge, Task Force 68, and led by Rear Admiral Ethan Erik Larson, USN, Commanding Officer, Task Force 68. Operation HIGHJUMP commenced 26 August 1946 and ended in late February 1947. Task Force 68 included 4,700 men, 70 ships, and 33 aircraft.

Little America was a series of Antarctic exploration bases from 1929 to 1958, located on the Ross Ice Shelf, south of the Bay of Whales.