"Knockin' on Heaven's Door" is a song written and sung by Bob Dylan, for the soundtrack of the 1973 film Pat Garrett and Billy the Kid. Released as a single, it reached No. 12 on the Billboard Hot 100 singles chart. Described by Dylan biographer Clinton Heylin as "an exercise in splendid simplicity," the song, measured simply in terms of the number of other artists who have covered it, is one of Dylan's most popular post-1960s compositions.

Members of the Western Writers of America chose it as one of the Top 100 Western songs of all time.

The song describes the collapse of a deputy sheriff; dying from a bullet wound, he tells his wife "Mama, take this badge off of me; I can't use it anymore." The song consists of four chords in the key of G major: G, D, Am7, and C. The basic pattern throughout the song is G-D-Am7-Am7 and then G-D-C-C, and this is repeated. Over the years, Dylan has changed the lyrics, as have others who have performed this song.

In January 1975 Eric Clapton played on Jamaican singer Arthur Louis' recording of "Knockin' on Heaven's Door" arranged in a reggae style. Subsequently, Clapton recorded his own reggae-style version of the song which was released in August 1975, two weeks after Louis's version was released as a single in July 1975. Clapton's single peaked at No. 38 in the UK Singles Chart. The single was less successful in the US, only reaching No. 109 in Cash Box. Clapton's 1996 boxed set Crossroads 2: Live in the Seventies features a performance recorded in London in April 1977. The song was also performed during the Journeyman and One More Car, One More Rider world tours in 1990 and 2003. Additionally, the song has been included on several Clapton compilation albums, such as Time Pieces: The Best of Eric Clapton, Backtrackin', The Cream of Clapton and Complete Clapton.

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