Lewis Allan Reed (March 2, 1942 – October 27, 2013) was an American musician and songwriter. He was the guitarist, singer, and principal songwriter for the rock band The Velvet Underground and had a solo career that spanned five decades. Although not commercially successful during its existence, the Velvet Underground came to be regarded as one of the most influential bands in the history of underground and alternative rock music. Reed's distinctive deadpan voice, poetic and transgressive lyrics, and experimental guitar playing were trademarks throughout his long career.

Having played guitar and sung in doo-wop groups in high school, Reed studied poetry at Syracuse University under Delmore Schwartz, and served as a radio DJ, hosting a late-night avant garde music program while at college. After graduating from Syracuse, he went to work for Pickwick Records in New York City, a low-budget record company that specialized in sound-alike recordings, as a songwriter and session musician. A fellow session player at Pickwick was John Cale; together with Sterling Morrison and Angus MacLise, they would form the Velvet Underground in 1965. After building a reputation on the avant garde music scene, they gained the attention of Andy Warhol, who became the band's manager; they in turn became something of a fixture at The Factory, Warhol's art studio, and served as his "house band" for various projects. The band released their first album, now with drummer Moe Tucker and featuring German singer Nico, in 1967, and parted ways with Warhol shortly thereafter. Following several lineup changes and three more little-heard albums, Reed quit the band in 1970.

After leaving the band, Reed would go on to a much more commercially successful solo career, releasing twenty solo studio albums. His second, Transformer (1972), was produced by David Bowie and arranged by Mick Ronson, and brought him mainstream recognition. The album is considered an influential landmark of the glam rock genre, anchored by Reed's most successful single, "Walk on the Wild Side". After Transformer, the less commercial but critically acclaimed Berlin peaked at No. 7 on the UK Albums Chart. Rock 'n' Roll Animal (a live album released in 1974) sold strongly, and Sally Can't Dance (1974) peaked at No. 10 on the Billboard 200; but for a long period after, Reed's work did not translate into sales, leading him deeper into drug addiction and alcoholism. Reed cleaned up in the early 1980s, and gradually returned to prominence with The Blue Mask (1982) and New Sensations (1984), reaching a critical and commercial career peak with his 1989 album New York.

Reed participated in the re-formation of the Velvet Underground in the 1990s, and he made several more albums, including a collaboration album with John Cale titled Songs for Drella, which was a tribute to their former mentor Andy Warhol. Magic and Loss (1992) would become Reed's highest-charting album on the UK Albums Chart, peaking at No. 6.

He contributed music to two theatrical interpretations of 19th-century writers, one of which he developed into an album titled The Raven. He married his third wife Laurie Anderson in 2008, and recorded the collaboration album Lulu with Metallica. He died in 2013 of liver disease. Reed has been inducted into the Rock and Roll Hall of Fame twice: as a member of the Velvet Underground in 1996 and as a solo act in 2015.