George Musarurwa Gregan AM (born 19 April 1973) is a former rugby union player who played as scrum-half. Born in Lusaka, Zambia, Gregan represented Australia at an international level, and is Australia's second most capped player.

He played in the Super 12 for the Brumbies from the inception of that competition in 1996 through 2007, helping to lead them to overall victories in 2001 and 2004. He is a foundation Brumbies player and his career spanned both the amateur and professional eras. As a member of the Wallabies team, Gregan won the Rugby World Cup in 1999. His time as Australian captain included a Bledisloe Cup win in 2002 and an extra-time loss to England in the 2003 Rugby World Cup final. Gregan and his longtime Wallabies teammate, fly-half Stephen Larkham, also hold the all-time record for Test appearances by a halfback partnership with 79.

Gregan was born in Zambia to an Australian father and a Zimbabwean mother, coincidentally in the same hospital where Corné Krige, who became the South Africa captain during Gregan's Wallabies captaincy, was born two years later. His family moved to Australia when he was two years old. He grew up in Canberra where he was educated at St Edmund's College, and graduated with a Bachelor of Education (Physical Education) from the University of Canberra.

Gregan and his wife Erica have three children, Max, Charlie and Jazz. Max was diagnosed with epilepsy in 2004; after spending time with Max in hospital and "[experiencing] firsthand the needs of many sick children and their parents" they set up the George Gregan Foundation in 2005. After building playgrounds in NSW, ACT and Qld hospitals and supporting the work of 18 neurology fellows, it is slated to close down in 2021.

Gregan represented Australia at under-19 and under-21 level.

Gregan made his first appearance for the Wallabies in 1994 in a match against Italy in Brisbane, which the Wallabies won 23 to 20. He was subsequently capped in the victories over Italy again, and Western Samoa.

Later in 1994, Gregan made a famous try-saving tackle on All Black Jeff Wilson that directly led to Australia winning the Bledisloe Cup that year and is much remembered as one of the greatest moments in the Wallabies-All Blacks rivalry. After two caps against Argentina the following season, Gregan had so far been on the winning side in all of his international games as Australia entered the 1995 World Cup in South Africa as defending champions. However, Australia made their exit at the quarter finals, losing 25 to 22 to England at Newlands in Cape Town.

The game went professional post-1995 World Cup, and one outcome of this was the formation of the Super 12, of which Gregan became a foundation player for the ACT Brumbies franchise. That season Gregan appeared eight times for the Wallabies, including solid wins over both Wales and Canada in Brisbane, scoring a try in the Canadian clash. Another outcome of professionalism was the formation of the Tri Nations Series between Australia, New Zealand and South Africa. Gregan played in three of Australia's four fixtures at the first ever tournament, scoring a try in the 25 to 32 loss to the All Blacks in Brisbane.