One of six submarines ordered by the RAN during the 1960s, Orion, named after the constellation in a break from ship-naming tradition, was built in Scotland and commissioned in 1977.

[9] Between 1977 and 1985,[clarification needed] the Australian Oberons were upgraded to carry United States Navy Mark 48 torpedoes and UGM-84 Sub Harpoon anti-ship missiles.

[11] Orion was laid down by Scotts Shipbuilding and Engineering Company at Greenock, Scotland on 6 October 1972, launched on 16 September 1974, and commissioned into the RAN on 15 June 1977.

[12] The delay meant that the two boats could be fitted with Micropuffs rangefinding sonar during construction, and have additional electronic surveillance equipment installed.

[16] As Orion and Otama were fitted with specialist intelligence gathering equipment, they were regularly deployed on surveillance and spying operations, earning them the nickname "Mystery Boats".

Orion and Otama would remain just off the horizon—around five nautical miles from a target—at periscope depth to observe surroundings and record information during operations close to enemy waters.

In 1987, Orion was awarded the Gloucester Cup, for being the RAN vessel demonstrating the greatest overall efficiency over the previous twelve months.

Conducted between 1978 and 1992, these operations involved intelligence-gathering missions off the coasts of Vietnam, Indonesia, China and India, primarily targeting the Soviet Navy during the Cold War.

[21] Efforts to hand her over to a state government for preservation as a museum ship or sinking as a dive wreck failed, and submissions for disposal companies were closed off on 6 August 2004.

In November 2011, authorisation was granted to establish a new Australian Naval Cadets unit in Jindabyne, New South Wales, named New Training Ship (NTS) Orion after the submarine.