"Back Door Man" is a blues song written by Willie Dixon and recorded by Howlin' Wolf in 1960. It was released in 1961 by Chess Records as the B-side to Wolf's "Wang Dang Doodle" (catalog no. 1777). The song is considered a classic of Chicago blues.

In Southern culture, the phrase "back-door man" refers to a man having an affair with a married woman, using the back door as an exit before the husband comes home. "When everybody trying to sleep, I'm somewhere making my midnight creep / Every morning the rooster crow, something tell me I got to go / I am a back door man," Wolf sings. The promiscuous "back-door man" is a theme of many blues songs, including those by Charley Patton, Lightnin' Hopkins, Blind Willie McTell and Sara Martin: "every sensible woman got a back-door man," Martin wrote in "Strange Loving Blues" (1925).Led Zeppelin referred to the Dixon song in "Whole Lotta Love" (1969) ("Shake for me girl, I want to be your back-door man") and in "Since I've Been Loving You" (1970) ("You must have one of them new fangled back door men!").

The song was recorded in Chicago in June 1960 by Howlin' Wolf (vocals), Otis Spann (piano), Hubert Sumlin and Freddy Robinson (guitars), Willie Dixon (double bass), and Fred Below (drums). The chord progression in the refrain of the song, similar to that found in Bo Diddley's "I'm a Man" (1955), John Lee Hooker's "I'm Mad (Again)" (1957), and Dixon's "Hoochie Coochie Man" (1954), dates back to work songs sung during the construction of train tracks. "Back Door Man" was included on the 1962 Wolf compilation album Howlin' Wolf. He re-recorded the song in November 1968 for The Howlin' Wolf Album.

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