Kozue Amano was born on May 26, 1974 in Saitama Prefecture, Japan. She began her professional career as a manga artist after winning an honorable mention in the sixth Big Rookie Award in 1993 for her short work Earth, making her professional debut the following year with the short story Zen'yasai. She is widely recognized as the creator of the best-selling series Aria.

Amano first achieved serialization with Roman Club, which ran from 1995 to 1996 in Monthly Shonen Gangan. This was followed by Crescent Noise, serialized in Monthly GFantasy from 1997 to 2001. However, her most significant commercial and critical success began with AQUA, which launched in 2001 in the magazine Monthly Stencil. Due to internal publishing issues at Enix, the series moved to Mag Garden's Monthly Comic Blade, where it was renamed and continued as ARIA from 2002 to 2008. The series became a best-selling hit and is her most famous work. After Aria concluded, she launched Amanchu! in 2008, which ran until 2021. Following a period of reduced output due to pregnancy and childcare, her publication schedule shifted from monthly to seasonal beginning in autumn 2010. In 2022, she began her latest ongoing series, Colori Colore Creare.

The Aria franchise has seen extensive adaptation into animation. The original manga was adapted into an anime television series spanning three seasons. It was also followed by several films and original video animations, including Aria the OVA ~Arietta~ (2007), Aria the Avvenire (2015), Aria the Crepuscolo (2021), and Aria the Benedizione (2021), for each of which Amano is credited as the original story creator. Her later work, Amanchu!, was also adapted into an anime television series in 2016.

Her artistic identity is defined by a distinctive style that creates a relaxed, peaceful atmosphere. She is known for her skillful expression of emotion, particularly through the detailed rendering of her characters' eyes. Her narratives often focus on the slow, idyllic passage of time and the discovery of happiness in daily life, a tone frequently described as healing or comforting. A notable personal passion that frequently appears in her work is her love for cats. She famously named the Aria Company after one of her pet cats, and her author photos in collected volumes are typically pictures of her feline companions. Her hobbies include shopping and playing video games such as Dragon Quest and Final Fantasy, and she has a noted ability to sleep while standing.