The Merchant Service Guild of Australia was first known as the Mercantile Marine Officers' Association. A General Meeting of members held on 12 February 1904 agreed to adopt the name Merchant Service Guild of Australasia. The Guild was registered under the Commonwealth Conciliation & Arbitration Act of 1904 on 5 May 1905 and the Victorian Branch was the first to be established in 1905. On 3 September 1957 the name of the union was changed slightly to the Merchant Service Guild of Australia and in 1992 it merged with the Australian Stevedoring Supervisors' Association to form the Australian Maritime Officers' Union