Alun (pronounced [ˈalɨ̞n]) is a Welsh variant of the masculine given name Alan. Notable people with the name include:
- Ailín I, Earl of Lennox, also spelled Alún, 12th century ruler of Lennox, Scotland
- Alun Anderson (born 1948), Welsh journalist
- Alun Armstrong (disambiguation)
- Alun Cairns (born 1970), Welsh politician
- Alun Davies (disambiguation)
- Alun Evans (disambiguation)
- Alun Francis (born 1943), Welsh conductor
- Alun Hoddinott (1929–2008), Welsh composer of classical music
- Alun Jones (disambiguation)
- Alun Lewis (disambiguation)
- Alun Michael (born 1943), Welsh politician
- Alun Owen (1925–1994), British screenwriter best known for the screenplay of The Beatles' film A Hard Day's Night
- Alun Pask (1937–1995), Wales international rugby union player and captain
- Alun Pugh (born 1955), Welsh politician
- Alun Thomas (1926–1991), rugby union player for Wales
- John Blackwell (Alun) (1797–1841), Welsh-language poet who used the bardic name Alun