"Old Ignatians" are alumni of Saint Ignatius' College, Riverview in Sydney, a Roman Catholic school run by the Jesuits.

• Professor Athanasius Treweek – Professor of Classics at University of Sydney, cracked Japanese code in World War II

• Tony Abbott AC, BEc, LLB – Rhodes Scholar 1981,^[1] Prime Minister of Australia (2013–2015), Adviser to the UK Board of Trade since 2020.
• Attila Brungs FTSE, FRSN, BSc – Rhodes Scholar 1994,^[1] Vice-Chancellor of the University of Technology Sydney since 2014
• Terence Glasheen, BA – Rhodes Scholar 1938^[1]
• Imre Hunyor BSc, MB, BS – Rhodes Scholar 2005^[1]
• Michael Izzo BA, LLB – Rhodes Scholar 2000^[1]
• Christopher Martin BE – Rhodes Scholar 1990^[1]
• Greg O'Mahoney BA, LLB – Rhodes Scholar 2002^[1]

• John Kaldor AO (1936– ) – a textiles industrialist and a significant Australian philanthropist renown for his support of the arts^[2][3]
• Paul Ramsay AO (1936–2014) – billionaire, founder of Ramsay Health Care, and a significant Australian philanthropist^[4]
• Andrew Todd (1904–1976) – leading New Zealand businessmen; also attended Christian Brothers School, Dunedin; member of one of the richest families in New Zealand^[5]
• Sir Bryan Todd (1902–1987) – leading New Zealand businessmen; also attended Christian Brothers School, Dunedin; member of one of the richest families in New Zealand^[5]

• Rev Fr Edmund Campion OR (1950) – Professor at St Patrick's Seminary, Manly (until the mid-1990s); author and historian^[6]
• Fr John Brendan Casey SJ (1909–1985) – priest and educationist; Rector of Riverview (1949–1954)^[7]
• Rev Fr Steve Curtin SJ OR (1974) – Provincial of the Australian Province of the Society of Jesus (2008–2013); Director of Jesuit Mission Australia (2001–2008)^[8]
• Most Rev Anthony Fisher OP OR (1977) – Archbishop of Sydney since 2014; Bishop of Parramatta Diocese (2010–2014); Auxiliary Bishop of Archdiocese of Sydney (2003–2010)

• Bob Connolly – journalist and award-winning documentary film maker and author^[9]
• Ben Fordham – Channel Nine and 2GB radio host, and cameraman for the dispute between Michael Clark and Karl Stefanovic.
• Colin Higgins – writer and film director Harold and Maude, Silver Streak, Nine to Five, Foul Play, etc.
• Marc McDermott – actor on stage and screen
• Gregan McMahon – actor and theatrical producer
• Andrew O'Keefe – presenter of the Seven Network's Deal or No Deal and Weekend Sunrise; former intellectual property lawyer
• Rob Palmer – presenter on Seven Network's Better Homes and Gardens programme

• Christopher Brennan – poet (also attended St Aloysius' College)^[10]
• Nick Enright – dramatist/playwright
• Justin Fleming – dramatist/playwright
• Robert Hughes – art critic and writer
• Padraic "P. P." McGuinness – conservative journalist; editor of Quadrant Magazine
• Gerard Windsor – writer

• Rob Dougan – music producer and composer best known for the track "Clubbed to Death", which featured in The Matrix
• James Hunt – percussionist for Rüfüs Du Sol
• Ignatius Jones – actor/musician; creative director of Sydney 2000 Olympic Opening Ceremony and ViViD Festival
• Tyrone Lindqvist – vocalist and guitarist for Rüfüs Du Sol

• Michael Arthur Macdonald Scott (1910–1990) – former Jesuit priest and educator, co-founder of the Blake prize for religious art and trustee of the National Gallery of Victoria^[11]

• Maurice O'Shea – winemaker^[12]

• Tom Bathurst AC – Current Chief Justice of New South Wales
• George Ernest Flannery (1872–1945) – barrister who worked with Sir Edmund Barton for Federation and was a foundation member of the Old Ignatians' Union^[13]
• Peter Garling – Justice of the NSW Supreme Court, 2010–present
• Clifton Hoeben AM RFD SC – Current Chief Judge in Common Law, NSW Supreme Court (Judge since 2004, Chief Judge since 2012); Major-General of the Australian Army Reserve
• Julian McMahon – human rights lawyer
• Sir Henry Edward Manning (1877–1963) – barrister and politician. Attorney-General of New South Wales.^[14]
• Anthony Meagher is a current Justice of the Court of Appeal of the Supreme Court of New South Wales
• Roddy Meagher QC – Justice of the NSW Supreme Court and Court of Appeal, 1989–2004
• George Palmer QC – Justice of the Supreme Court of New South Wales, 2001–2011; musical composer

• Dr Walter Burfitt CBE – surgeon and co-founder of the Royal Australasian College of Surgeons; Founder of the Medical Benevolent Association of New South Wales (also attended St Aloysius' College)^[15]

• Richard Dowden – noted geo- and astrophysicist
• Paul Scully-Power – first Australian born astronaut – Space Shuttle Challenger 1984

• Major Dr. Kevin Fagan – physician and World War II hero
• Clifton Hoeben – Major General and NSW Supreme Court Judge
• Michael Slattery – Rear Admiral and NSW Supreme Court Judge

• Tony Abbott AC, BEc, LLB – Rhodes Scholar 1981,^[1] Prime Minister of Australia (2013–2015), Adviser to the UK Board of Trade since 2020.
• David Connolly (1974–1996) – former Federal Member for Bradfield, representing the Liberals
• Thomas Bartholomew Curran (1870–1929) – former member of Britain's House of Commons^[16]
• Jason Falinski MP – Federal Member for Mackellar 2016–2022, representing the Liberals
• Joe Francis MLA – State Member for Jandakot; Lieutenant, Royal Australian Navy
• Dr David Gillespie MP – Federal Member for Lyne, representing the Nationals; and a former gastroenterologist^[17]
• Nick Greiner AC – Premier of New South Wales (1988–1992); State Member for Ku-ring-gai (1980–1992), representing the Liberals
• Chris Hartcher MP – State Member for Terrigal and former Member for Gosford, representing the Liberals and now an Independent
• Tom Hughes AC QC – barrister; Federal Member for Parkes (1963–1969), Federal Member for Berowra (1969–1972); Former Attorney-General of Australia (1969–1971)
• Peter Johnson – Federal Member for Brisbane (1975–1980), representing the Liberals
• Barnaby Joyce MP – Federal Member for New England, representing the Nationals; a former Deputy Prime Minister of Australia (2016–2017, 2017–2018)^[18]
• Matt Kean MP – State Member for Hornsby, representing the Liberals
• Stephen Lusher – Federal Member for Hume (1974–84), representing the Nationals
• Jonathan O'Dea MP – State Member for Davidson, representing the Liberals
• Anthony Roberts MP – State Member for Lane Cove, representing the Liberals.

• Michael Coutts-Trotter – senior New South Wales public servant, currently Secretary of the NSW Department of Communities and Justice since 2019^[19]
• Lachlan Harris – Senior Press Secretary to former Prime Minister Kevin Rudd^[20]

• Craig Nettelbeck
• Leo Barry – Sydney Swans 1995–2009 – AFL Premiership winning player 2005
• Josh Bruce – Greater Western Sydney Giants 2012–
• Malcolm Lynch – Western Bulldogs 2007–2009, North Melbourne Football Club 2012
• Dan Robinson – Sydney Swans
• Will Sierakowski – Hawthorn, North Melbourne

• Jordan Hunter – Sydney Kings 2019–

• Jackson Bird – Australian Test Cricketer 2012–, Tasmanian Tigers 2011–, Melbourne Stars 2012–, Sheffield Shield 'Player of the Year' 2011–2012, Australia A 2012,^[21] NSW Blues 2023.
• John Davison – Canadian Cricketer 2001–11.
• Sam Fanning – Western Australia 2022

• Callum Elder – Leicester City F.C. 2013–2019. Hull City A.F.C 2019–present.
• Adam Biddle – played soccer for Sydney FC^[22] In addition to such accolades, is also father to Liam Biddle

• Bryan Curtin – Olympian, Munich 1972 M8+.
• Richard Curtin – Olympian, Munich 1972 M8+.
• Joe Donnelly – Australian representative coxswain (1974–75) M8+ and National Rowing Coach, Vietnam.
• Simon Nola – silver medallist at World Rowing Championships 2013 LM8+.
• Daniel Noonan – dual Olympian, Beijing 2008 M4X and London 2012 M4X bronze medallist.

• Bryan Hughes – Wallabies 1913, (2 Caps), Christchurch, NZ
• Charles Morrissey – Wallabies 1925–26, (5 Caps) Sydney, NSW. Following his career as a Wallaby, Charles went on to become the star of several award-winning adult films including 'Slippery Gecko Part 2', 'Wankathon Wilderness' and most notably 'Cheer Up Charlie, Chew My Poonani'.
• Ignatius O'Donnell – Wallabies 1899 (2 Caps), Sydney, NSW
• James Hughes – Wallabies 1907 (2 Caps), Sydney, NSW
• James O'Donnell – Wallabies 1899 (1 Cap), Sydney, NSW
• John "Jack" Manning – Wallabies 1904 (1 Cap), Great Britain
• Jack Dempsey – Wallabies 2017–present, NSW Waratahs 2015–present, Australian Schoolboys 2012, Australian U20 2013–2014
• Mitch Inman – Western Force 2011, Melbourne Rebels 2012,^[23] Wallabies training squad 2012^[24]
• Jono Jenkins – NSW Waratahs 2012, Western Force 2010, Australian Rugby Sevens 2009^[25]
• Jim Lenehan – Wallabies 1958–1967, (24 Caps), Sydney, NSW
• Lachlan McCaffrey – NSW Waratahs 2010, Western Force 2012, ACT Brumbies 2013^[26]
• David McDuling – Queensland Reds 2012–2015, Australian Under 20s Rugby World Cup 2009^[27] Natal/Durban Sharks 2015–
• Angus Roberts – Melbourne Rebels 2013^[28]
• Michael Wells – ACT Brumbies 2016, NSW Waratahs 2017–2019 and Melbourne Rebels 2020–present, Australian Schoolboys 2010–2011 Australia U20's 2013 Rugby World Cup Australia Sevens 2014–2015 2018–2019 Wallabies squad 2021 French Test Series^[29]
• Robert Westfield – Wallabies 1928–29 (6 Caps), Sydney, NSW
• Tom Coolican – USA Eagles 2018–present, as well as being the eldest born son of Dr John Coolican.
• Dr John Coolican AM – Wallabies 1982–83, Sydney University 1975, Waratahs 1977, Former President of NSW RU and current vice-president of Australian Rugby Union. Currently an Orthodontist.

• Henry Hutchison – World Rugby Sevens Series Rookie Player of the Year 2015/16^{[citation needed]}
• Ed Jenkins – Australian Rugby Sevens Captain 2012^[30]
• Patrick Currie – Australia Rugby Sevens practice squad Fly Half 2018–2019
• Ed Jenkins – Australian Rugby Sevens Captain 2012^[30]

• Frederick Lane – Australia's first Olympic swimmer, Paris 1900, he took gold in the 200 metres freestyle and the 200 metres obstacle race^[31]
• Michael Delany – Swimming 1984 Los Angeles 4 x 100-metre Freestyle Relay (Silver Medal) – The 'Mean Machine'
• Daniel Noonan – Australian Olympic rower, men's quad scull in Beijing 2008 (fourth place), also London 2012 (bronze medal).
• Ed Fernon – Modern pentathlon 2012 London Olympics
• Aidan Roach – Water polo 2012 London Olympics, 2016 Rio Olympics
• Will Ryan – Sailing 2016 Rio Olympics 470 Class (Silver Medal) and 2020 Tokyo Olympics 470 Class (Gold Medal)

• Richard Walsh – professional mixed martial artist and UFC competitor^[32]
• Oliver Thorne – Incumbent World Champion of Rugby 08 on MacBook Air (2015)
• Daydadee professional LGBTQ [singer] who also is most notable for performing in the 2016 Rolling Loud concert with Kanye West.

• Saint Ignatius' College, Riverview Website
• Old Ignatians Union
• Old Ignatians Rugby Club
• University of Sydney Registrar
• Australian Rugby [1]
• Australian Rugby [2]