The Leeuwin class is a two-ship class of hydrographic survey vessels operated by the Royal Australian Navy (RAN). Leeuwin and Melville were ordered from NQEA Australia in 1996, and were commissioned in 2000. The ships are capable of charting waters up to 6,000 metres (20,000 ft) deep, carry three Fantome-class survey boats, and could operate an AS 350B Squirrel helicopter. In addition to surveying duties, since 2001 both vessels have been used to supplement the RAN patrol force. Leeuwin and Melville are based at HMAS Cairns, and are active as of 2023.

The Royal Australian Navy (RAN) is the naval force of the Australian Defence Force (ADF). The professional head of the RAN is Chief of Navy (CN) Vice Admiral Mark Hammond AM, RAN. CN is also jointly responsible to the Minister of Defence (MINDEF) and the Chief of Defence Force (CDF). The Department of Defence as part of the Australian Public Service administers the ADF.