Alan Kennedy (born 31 August 1954) is an English former professional footballer who played the majority of his career as a left back for Newcastle United and then Liverpool. He was a stalwart member of the latter team that won many honours from the late 1970s to the mid-1980s. At different times Kennedy was active as a professional in England, Denmark, Belgium and Wales, making over 500 appearances in a career that lasted for 22 years. He also represented England at senior international level.

Born in Sunderland, Kennedy started his professional career at the age of 18 for Newcastle United. After establishing his place in the side he played there for five years. He was a member of the teams that lost the 1974 FA Cup Final to Liverpool and the 1976 League Cup Final to Manchester City. In 1978 he was transferred to Liverpool for £330,000, at the time a British record amount for a full-back.

Kennedy scored in the 1981 League Cup Final against West Ham, which ended 1–1 and was won by Liverpool in the replay. He scored the equalising goal with 15 minutes left in the game in the 1983 League Cup Final against Manchester United, a match Liverpool went on to win in extra time. Kennedy was a member of two other League Cup–winning Liverpool teams: in 1982 (against Tottenham Hotspur) and 1984 (against Everton).

In the 1981 European Cup Final against Real Madrid, Kennedy scored the only goal of the match late in the second half.

The 1984 European Cup Final between Liverpool and Roma was tied at 1–1 after extra time, so the winner was determined by penalty kicks. Kennedy scored the decisive penalty (the fifth taken by the team, the fourth that was successful) that clinched the victory for Liverpool.

Kennedy was a regular player in the Liverpool teams that won five league championship titles, in 1978–79, 1979–80, 1981–82, 1982–83 and 1983–84.

He also earned two caps for the England national team in 1984.

His elder brother is fellow footballer Keith Kennedy. His nephew is Tom Kennedy, Keith's son.