Notable people and characters named Sydney include:

Given name

Men

• Sydney Allard (1910–1966), British car company founder
• Sydney Ancher (1904–1978), Australian architect
• Sydney Arnold, 1st Baron Arnold (1878–1945), radical British Liberal Party politician
• Sydney Atkinson (1901–1977), South African athlete
• Sydney D. Bailey (1916–1995), English author and pacifist
• Sydney Barnes (1873–1967), English cricketer
• Sydney Beaumont (1884–1939), English professional footballer and football manager, runner and cricketer
• Sydney Brenner (1927–2019), South African biologist
• Sydney Brown (American football) (born 2000), Canadian American football player
• Sydney Savory Buckman (1860–1929), British paleontologist
• Sydney Burdekin (1839–1899), Australian politician
• Sydney Butchkes (1922–2015), American visual artist and designer
• Sydney Buxton, 1st Earl Buxton (1853–1934), radical British Liberal politician
• Sydney Caine (1902–1991), English educator and economist
• Sydney Camm (1893–1966), English aeronautical engineer
• Sydney Carline (1888–1929), British artist and teacher
• Sydney Chaplin (1885–1965), English actor
• Sydney Earle Chaplin (1926–2009), American actor
• Sydney Chapman, multiple people
• Sidney Chu (born 1999), Hong Kong short track speed skater
• Syd Cohen, American baseball pitcher
• Sydney Dacres (1805–1884), English admiral
• Sydney de Zoysa (1909–1994), Sri Lankan Sinhala police officer
• Sydney Thompson Dobell (1824–1874), English poet and critic
• Sydney Dodd (c. 1874–1926), British veterinary surgeon and scientist
• Sydney Donkin (1871–1952), British civil engineer
• Sydney Dowse (1918–2008), Royal Air Force pilot
• Sydney "Syd" Einfeld (1909–1995), Australian politician and Jewish community leader
• Sydney F. Foster (1893–1973), Chief Judge of the New York Court of Appeals
• Sydney Fremantle (1867–1958), English admiral
• Sydney Gardner (1884–1965), Australian politician
• Sydney Gedge (1829–1923), British Conservative politician
• Sydney Greenstreet (1879–1954), English actor
• Sydney Grundy (1848–1914), English dramatist
• Sydney Gun-Munro (1916–2007), Saint Vincent and the Grenadines politician
• Sydney J. Harris (1917–1986), American journalist
• Sydney Herring (1881–1951), Australian Army colonel and temporary brigadier general in the First World War
• Sydney Hinam (1898–1982), Welsh rugby union and professional rugby league footballer
• Sydney Holland, 2nd Viscount Knutsford (1855–1931), British barrister and peer
• Sydney Horler (1888–1954), British novelist
• Sydney Jacobson, Baron Jacobson (1908–1988), British journalist
• Sydney Jary (1924–2019), British Army officer
• Sydney Josland (1904–1991), New Zealand bacteriologist
• Sydney Kentridge (born 1922), South African lawyer and judge
• Sydney Lamb (born 1929), American linguist
• Sydney Laurence (1865–1940), American painter
• Sydney Lipton (1905–1995), British dance band leader
• Sydney McMeekan (1925–1991), British basketball player
• Sydney Mufamadi (born 1959), South African politician
• Sydney Newman (1917–1997), Canadian film and television producer
• Sydney A. Oades (1890–1961), British World War I flying ace
• Sydney Olivier, 1st Baron Olivier (1859–1943), British civil servant
• Sydney Omarr (1926–2003), American astrologist
• Sydney Paget (1857–1916), English aristocrat
• Sydney Parkinson (1745–1771), Scottish illustrator
• Sydney Pollack (1934–2008), American film actor
• Sydney Possuelo (born 1940), Brazilian explorer and ethnographer
• Sydney Ringer (1836–1910), British pharmacologist
• Sydney Rowell (1894–1975), Australian soldier, Chief of the General Staff from 1950 to 1954
• Sydney Domville Rowland (1872–1917), English physician
• Sydney Schanberg (1934–2016), American journalist
• Sydney Segal (1920–1997), Canadian pediatrician and neonatologist
• Sydney Sekeramayi (born 1944), Zimbabwean politician
• Sydney Selwyn (1934–1996), British physician, medical scientist, and professor
• Sydney Shearer (1890–1973), New Zealand rugby union player
• Sydney Shoemaker (1931–2022), American philosopher
• Sydney Silverman (1895–1968), British politician
• Sydney Simmons (1840–1924), British entrepreneur and philanthropist
• Sydney Vincent Sippe (1889–1968), British pioneer aviator
• Sydney Skaife (1889–1976), South African entomologist
• Sydney Smirke (1798–1877), English architect
• Sydney Smith (1771–1845), English writer
• Sydney Tafler (1916–1979), English actor
• Sydney Taylor (1904–1978), American author
• Sydney Templeman, Baron Templeman (1920–2014), British judge
• Sydney James Van Pelt (1908–1976), Australian medical practitioner
• Sydney J. Van Scyoc (1939–2023), American science fiction writer
• Sydney Curnow Vosper (1866–1942), English painter
• Sydney Rigby Wason (1887–1969), senior British Army officer in the Second World War
• Sydney Wignall (1922–2012), British marine archaeologist, climber, explorer and spy
• Sydney Wilson (born 1990), English former professional snooker player
• Sydney Wooderson (1914–2006), English athlete
• Sydney Youngblood (born 1960), American-German singer, actor and composer

Women

• Sydney Baldwin (born 1996), American ice hockey defender
• Sydney Barros (born 2005), American artistic gymnast
• Sydney Blomquist (born 1993), American professional soccer player
• Sydney Cummings (born 1999), American-born Guyanese professional footballer
• Sydney Fairbrother (1872–1941), British actress
• Sydney Kamlager (born 1972), American politician
• Sydney Kolodziej (born 1993), American pair skater
• Sydney Land (1995–2016), American victim of unsolved shooting
• Sydney Leroux Dwyer (born 1990), Canada-born American soccer player
• Sydney Magruder Washington, American ballet dancer and blogger
• Sydney Mancasola, American opera soprano
• Sydney Mikayla (born 2003), American actress
• Sydney Morton (born 1985), American stage and television actress, singer and dancer
• Sydney Park (actress) (born 1997), American actress and comedian
• Sydney Parr, American softball player
• Sydney Penny (born 1971), American actress
• Sydney Tamiia Poitier (born 1973), Bahamanian-American actress, daughter of Sidney Poitier
• Sydney Pokorny (1965–2008), American lesbian writer, editor, columnist and activist
• Sydney Rossman (born 1995), American ice hockey player
• Sydney Sadick (born 1994), American on-air fashion and entertainment commentator
• Sydney Sierota (born 1997), lead singer of Echosmith
• Sydney Sweeney (born 1997), American actress
• Sydney Walsh (born 1961), American actress
• Sydney Rae White (born 1991), English actress and singer

Surname

• Algernon Sydney (1623–1683), English politician
• Berenice Sydney (1944–1983), English artist
• Grahame Sydney (born 1948), New Zealand artist
• Harry Sydney (born 1959), American football player
• Joan Sydney (1936–2022), English actress
• Robin Sydney (born 1984), American actress

Fictional characters

• Sydney Andrews, character in the television series Melrose Place
• Sydney Bristow, character in the television series Alias
• Sydney Carton, character in the novel A Tale of Two Cities
• Sydney Drew, character in the television series Power Rangers: S.P.D.
• Sydney Fox, character in the television series Relic Hunter
• Sydney Losstarot, character in the video game Vagrant Story
• Sydney Novak, character in the television series I Am Not Okay With This
• Sydney, character in the television series The Pretender
• Kevin Sydney, fictional character in the X-Men comic series