The Amalgamated Metal Workers Union originally formed in 1973 from the amalgamation of the Amalgamated Engineering Union, the Sheet Metal Working, Agricultural Implement and Stovemaking Industrial Union of Australia, the Boilermakers' and Blacksmiths' Society of Australia, and the Federated Jewellers. In 1976 the union amalgamated with the Federated Shipwrights' & Ship Constructors' Association of Australia to become the Amalgamated Metal Workers & Shipwrights Union. In 1983 it joined the Federated Moulders (Metals) Union of Australia to become the Amalgamated Metals Foundry and Shipwrights' Union. It reverted to the name Amalgamated Metal Workers' Union in 1985 and operated until 1991 when it amalgamated with the Association of Draughting Supervisory & Technical Employees to become the Metals & Engineering Workers' Union.

Metals & Engineering Workers' Union was formed from the amalgamation of the Amalgamated Metal Workers' Union and the Association of Draughting Supervisory & Technical Employees in 1991. It operated until 1993 when it was amalgamated with the Vehicle Builders Employees' Federation of Australia to become part of the Automotive Metals & Engineering Union.

The Australian Manufacturing Workers' Union (AMWU) was established in 1995 after the Automotive Food Metals and Engineering Union amalgamated with the Printing and Kindred Industries Union to become the Automotive Food Metals Engineering Printing and Kindred Industries Union, better known as the AMWU.