AUUG was an Australian association and users' group. It described itself as the organisation for Unix, Linux and Open Source professionals. Its aim was to build a community of those interested in open systems and open standards. The newsletter AUUGN is pronounced .

AUUG ran nationally with chapters in most states and territories. The main activities were a website, mailing lists, the AUUGN newsletter, various conferences, and chapter meetings.

Along with USENIX, AUUG was one of the oldest Unix user groups in the world. Founded in 1975 by John Lions and others as the Australian Unix systems User Group, it later broadened its remit but retained the name. It was constituted on 27 August 1984 and incorporated as "AUUG Inc" on 26 August 1988 in Victoria. AUUG was dissolved between 2010 and January 2015, though it had been in decline for years, and its members were asked to vote on whether to continue as early as 2007. There is an AUUG Preservation Society which took over management of the auug.org.au domain name in June 2011.

As of 9 January 2015, the Victorian Incorporated Association Register lists A0016636N (AUUG Inc) as Deregistered with its last return filed in 1995.