AUSSI was established in Sydney on the 22nd September 1975 by a group of eight men – Jack Brownjohn, John Kemp, Bill Lough, Alf Sparks, Frank Sykes, Gary Stutsel, John Wainwright and Ray Weekes.

AUSSI is an acronym for:
    Union of

The New South Wales Branch was formed four weeks later, and since then branches have been formed in each of the other States.

At first membership was gained by joining a State Branch, but this proved unwieldy and so clubs were formed to act between members and their State Branch.

Masters Swimming Australia is affiliated with the world governing body of swimming, FINA, which regulates competition between swimmers of different countries.