It was built under license by Commonwealth Aircraft Corporation in the final stages of World War II, and though it was too late to see combat, it did participate in the Occupation of Japan after VJ-Day.

In December 1942, the Australian War Cabinet began looking to acquire a fighter aircraft with greater range than the Supermarine Spitfire.

80 of the kits were assembled under the designation CA-17 Mustang Mk 20 with Packard V-1710-3 Merlin engines, the remainder being used for spare parts.

In late 1946, CAC received a contract to build 170 (later reduced to 120) Mustangs locally from scratch.

[5] The first production CA-17 Mustang Mk 20, serial number A68-01 (not to be confused with the US-built prototype A68-1001), made its first flight on 29 April 1945 from Fishermans Bend.

The RAAF replaced its last Mustangs with de Havilland Vampires in 1959, while the last Mustang-equipped Citizen Air Force squadron, No.

[2] A full-scale replica of a CA-18 Mustang Mk 23 is located at the Queensland Air Museum at the Caloundra Airport.