Australian Hospital Ship (AHS) Centaur was a hospital ship active during World War II, which was attacked and sunk by a Japanese submarine in 1943. Of the 332 medical personnel and crew aboard, 268 died.

Centaur served in both civilian and military capabilities and during her career was involved in towing a damaged Japanese whale-chaser and recovering German survivors of the engagement between HMAS Sydney and HSK Kormoran.

Before dawn on 14 May 1943, while on her second voyage, Centaur was torpedoed and sunk by a Japanese submarine off North Stradbroke Island, Queensland. The majority of the 332 aboard died in the attack and the 64 survivors had to wait for 36 hours before they were rescued.

The attack resulted in public outrage as it was considered to be a war crime. Protests were made by the Australian and British governments to Japan and efforts were made to discover the people responsible so they could be tried at a war crimes tribunal. Despite this, it was not until 1979 that the attacking submarine, I-177, was identified.