St Gregory's College Campbelltown (abbreviated as SGC or Greg's or St Greg's) is an independent Catholic single-sex and co-educational comprehensive and specialist primary and secondary day and boarding school, located in Gregory Hills, near Campbelltown, a south-western suburb of Sydney, New South Wales, Australia.

Founded on 3 February 1926 and conducted by the Marist Brothers since 1929, St Gregory's has a non-selective enrolment policy and currently caters for approximately 1,100 students, including 180 boarders.

The college has hosted the Marist cricket and basketball Carnival's, Won the Arrive Alive and Nutri-Grain Cup.

In June, July and August 2014 the Royal Commission into Institutional Responses to Child Sexual Abuse initiated in 2013 by the Australian Government and supported by all of its state governments,[8] began an investigation into the response of Marist Brothers to allegations of child sexual abuse in schools in the ACT, NSW and Queensland.

[9] Five former students, one former teacher, a former assistant principal and two former principals, former and current Marist officials and clergy, and one of the clergy at the centre of the allegations gave evidence or made statements before the Royal Commission[10] that the alleged cases of abuse happened during the 1970s, and 1980s at Daramalan College, Canberra, at Lismore, Campbelltown and in Far North Queensland.

Previously, the land owned by the College once exceeded 405 hectares (1,000 acres) before most of it was sold to create the Gregory Hills housing sub-division,[16] located in the suburb of Gregory Hills (a suburb located within Camden Council) and approximately 43 kilometres (27 mi) from the Sydney central business district.

St Gregory's is located on Badgally Hill, the second highest peak between Sydney and the Great Dividing Range.

The college has been dubbed "A Nursery for Mens Water Polo Players" and with this Water Polo is very strong culture at the college as St Gregory's compete in the MCS competition and the Arrive Alive Cup and have been champions on a record 9 occasions and Runners Up twice.

Strong support from the college community is present at semi-finals and finals in the MCS competition and all Arrive Alive Cup matches.

On Grand Final day 2007 saw each 3 grandfinals Jersey Flegg, Premier League and the NRL Telstra Premiership had a representative from St Gregory's College.

Until 2008 the Year 12 debating trophy was named for Douglas Berneville-Claye a former teacher who was a convicted criminal and British traitor.

[19] Once based on 526 hectares (1,300 acres) and, until 1990, called "St Gregory's Agricultural College"[20] it was home to a commercial dairy, cattle, poultry, piggery and popular rodeo timed to coincide with the Fisher's Ghost Festival.

[21] The school began a land cost analysis in the late 1980s, assigning senior Agricultural students the task of identifying value as their major project for the HSC.