Furlong is an English-language surname, relatively common in the United Kingdom and in the Republic of Ireland.
Notable people with the surname include:
- Aaron Henry Furlong (born 1967), American jewellery designer
- Allan Furlong (born 1942), Canadian politician
- Campbell Furlong (born 1974), New Zealand cricketer
- Cathy Furlong, American statistician
- Charles W. Furlong (1874–1967), American explorer
- Darnell Furlong (born 1995), English footballer
- Dennis Furlong (1945–2018), Canadian politician
- Edward Furlong (born 1977), American actor
- Grant Furlong (1886–1973), American politician
- Jim Furlong (football) (born 1940), Canadian football linebacker
- John Furlong (American actor) (1933–2008), American actor
- John Furlong (Canadian) (born 1950), CEO of the Vancouver 2010 Olympic and Paralympic Winter Games
- Monica Furlong (1930–2003), British author, journalist and activist
- Nicholas Furlong (1929–2022), Irish journalist and historian
- Nicholas Furlong (musician) (born 1986), American singer, songwriter, and record producer
- Nicola Furlong, Canadian novelist
- Nicola Furlong, Irish murder victim in Japan
- Noel Furlong (1937–2021), Irish poker player
- Oscar Furlong (1927–2018), Argentine basketball player
- Paul Furlong (born 1968), English footballer
- Rob Furlong (born 1976), Canadian sniper who holds the record for the longest sniper kill in combat
- Tadhg Furlong (born 1992), Irish rugby player