Cave Glacier is an ice sheet on the east shore of Alexander Island, Antarctica, which streams east into George VI Sound between Belemnite Point and Ablation Point. It is 46 km (29 mi) long, 6 km (4 mi) wide where it rises up out of the waterfront mountains, and 13 km (8.1 mi) wide at its mouth. It was initially captured from the air on 23 November 1935, by Lincoln Ellsworth and mapped from these photos by W.L.G. Joerg. It was generally reviewed in 1936 by the British Graham Land Expedition and resurveyed in 1949 by the Falkland Islands Dependencies Survey (FIDS). The ice sheet was so named by the FIDS on the grounds that a sledge puppy was safeguarded from a cave likecrevasse in the icy mass.