Ai Yazawa was born on March 7, 1967, in Amagasaki, Hyogo Prefecture, Japan. After graduating from high school, she enrolled at the Osaka Mode Gakuen, a fashion school, though she left before completing her studies. Her career as a manga artist began in 1985 when she debuted with the short story Ano Natsu, published in the magazine Ribon. Her pen name is said to be inspired by the Japanese singer Eikichi Yazawa, of whom she is a fan.

Yazawa is the original creator behind numerous beloved manga series, many of which have been adapted into anime and live-action films. One of her early major successes was Tenshi Nanka ja Nai (I'm Not an Angel), a school romance serialized in Ribon from 1992 to 1995. Following that, she created Neighborhood Story (Gokinjo Monogatari), which was serialized in Ribon from 1995 to 1998. The manga was adapted into a fifty-episode anime television series produced by Toei Animation, which aired from September 1995 to September 1996, as well as an anime film released in March 1996.

The Neighborhood Story manga is set at the fictional Yazawa Art Academy and follows aspiring fashion designer Mikako Koda. The series is notable for introducing characters and settings that would reappear in Yazawa's later work, Paradise Kiss, creating a shared universe. Her other notable works include the three-volume series Kagen no Tsuki (Last Quarter), which was adapted into a live-action film in 2004, and the five-volume Paradise Kiss, which was serialized in the fashion magazine Zipper from 1999 to 2003 and later received an anime adaptation in 2005.

Yazawa is best known internationally for her series Nana, which began serialization in the magazine Cookie in 2000. Nana became one of the best-selling manga series of all time and earned Yazawa the Shogakukan Manga Award in 2003. The series was adapted into a celebrated anime by Madhouse and a successful two-part live-action film in Japan. In June 2009, Yazawa became ill and was hospitalized, placing Nana on an indefinite hiatus. She returned from the hospital in April 2010, but the series has remained on hold since then. She has occasionally contributed illustrations and short manga projects since the hiatus began.

A defining feature of Yazawa's artistic identity is her deep integration of fashion and music into her storytelling. She has stated that since manga cannot produce sound, fashion becomes an essential visual tool to express a character's world, particularly for stories about musicians and bands. She is known for drawing from her extensive personal collection of clothing, especially designs by Vivienne Westwood, to dress her characters. This attention to detail creates a distinctive, stylish aesthetic that is closely tied to the late 1990s and early 2000s Japanese street fashion and punk subcultures. Her storylines typically center on young women navigating complex relationships, pursuing dreams, and seeking their own definitions of happiness, with characters often portrayed as flawed and rebellious, juxtaposed against more traditional figures.

Ai Yazawa holds significant industry stature as a creator whose work has resonated with a wide audience, extending beyond typical readers of shoujo manga. Her series Nana, in particular, achieved mainstream popularity and critical acclaim, solidifying her legacy as one of the most influential manga artists of her generation. Even with her long-term hiatus, her works continue to find new fans and inspire creative endeavors, including fashion collaborations and re-releases.