"Brown Sugar" is a song by British rock and roll band The Rolling Stones. Though credited, like most Stones compositions, to Jagger/Richards, the song was primarily the work of singer Mick Jagger, who wrote it sometime during the filming of Ned Kelly in 1969. Originally recorded over a three day period at Muscle Shoals Studios in Alabama during December 1969, the song was not released until over a year later due to legal wranglings with the band's former label, though the Stones debuted the number live during the infamous concert at Altamont. In the film Gimme Shelter, an alternate mix of the song is played back to Mick and Keith while they relax in a hotel (possibly The Chelsea) in New York. This version differs from that on record by the inclusion of a rhythmic variation on the familiar staccato introduction for two out of every four bars for that part.

The song was performed steadily during the Stones' 1970 European Tour, occupying a prominent spot near the end of the set list even though audiences were unfamiliar with it. The song was eventually released in May 1971 as the first single from the album Sticky Fingers, becoming a number-one hit in the U.S. and a number two hit in the UK.

An alternate version was recorded December 19, 1969 at Olympic Studios in London, after (or during) a birthday party for Richards. It features appearances by Al Kooper on piano, and Eric Clapton on lead guitar. It also features Richards singing the first verse, and loudlybacking up the rest of the song. The alternate version is widely available on bootleg recordings. Richards considered releasing this version on Sticky Fingers, mostly for its more spontaneous atmosphere, but decided on the original.

The song, with its prominent blues-rock riffs, dual horn/guitar instrumental break, and danceable rock rhythms, is representative of the Stones' definitive mid-period and the tough, bluesy hard-rock most often associated with the group. The song was an immediate hit and has since become a classic rock radio staple and Stones concert stalwart, opening the famed 1972 American Tour shows and being played frequently ever since. However, its lyrical subject matter has often been a point of interest and controversy. Described by rock critic Robert Christgau as "a rocker so compelling that it discourages exegesis", "Brown Sugar"'s popularity indeed often overshadowed its scandalous lyrics, which were essentially a pastiche of a number of taboo subjects, including interracial sex, cunnilingus, slave rape, and less distinctly, sadomasochism, lost virginity, and heroin use. In the liner notes to the 1993 compilation disc Jump Back, Jagger says, "The lyric was all to do with the dual combination of drugs and girls. This song was a very instant thing, a definite high point." The song is often said to have been inspired by an encounter with "Ikette", Claudia Lennear.

When the Rolling Stones perform "Brown Sugar" live, Jagger often changes the lyrics from, "Just like a young girl should," to, "Just like a young man should." The line, "Hear him whip the women just around midnight," is often changed to the less offensive, "You shoulda heard him just around midnight." This is evidenced in their live albums Love You Live and Live Licks. This change even occurs on the version recorded at Keith's birthday party.

The song is also notable for being the first single released on Rolling Stones Records, and is one of the two Rolling Stones songs (along with "Wild Horses") licensed to both the band and former manager Allen Klein, a result of various business disagreements.

While the US single only featured "Bitch" on the B-side, the UK single featured that track plus a live rendition of Chuck Berry's "Let It Rock", recorded at Leeds University during the 1971 tour of the UK.