Kim Althea Gordon (born April 28, 1953) is an American musician, singer and songwriter, best known as the bassist, guitarist, and vocalist of alternative rock band Sonic Youth. Born in Rochester, New York, she was raised in Los Angeles, California, where her father was a professor at the University of California, Los Angeles. After graduating from Los Angeles's Otis College of Art and Design, she moved to New York City to begin an art career. There, she formed Sonic Youth with Thurston Moore in 1981. She and Moore married in 1984, and the band released a total of six albums on independent labels before the end of the 1980s. They would subsequently release nine studio albums on the major label DGC Records, beginning with Goo in 1990. Gordon was also a founding member of the musical project Free Kitten, which she formed with Julia Cafritz in 1993.

Sonic Youth released their sixteenth and final studio album, The Eternal (2009), on Matador Records before disbanding in 2011 after Gordon and Moore separated. Following the dissolution of Sonic Youth and her divorce from Moore, Gordon formed the experimental duo Body/Head with Bill Nace, releasing their debut album Coming Apart in 2013. She subsequently formed Glitterbust with Alex Knost, releasing a self-titled debut album in 2016. Body/Head released their second studio album, The Switch, in 2018. She released her first solo album, No Home Record, in 2019.

In addition to her work as a musician, Gordon has had ventures in record producing, fashion, and acting, and has worked consistently as a visual artist throughout her musical career. She debuted as a producer on Hole's debut album Pretty on the Inside (1991), and founded the Los Angeles-based clothing line X-Girl in 1993. Beginning in the mid-2000s, Gordon began acting, making minor appearances in such films as Last Days (2005) and I'm Not There (2007), followed by guest-starring appearances on several television series. In February 2015, she published a memoir, Girl in a Band, by HarperCollins imprint Dey Street Books.