Yoko Kamio was born on June 29, 1966 in Tokyo, Japan. She graduated from Tokyo Polytechnic University.
In 1986, Kamio debuted in Margaret with the short story, "Hatachi no mama de matteru" (はたちのままで待ってる). Kamio also published Ano Hi ni Aitai (1989), Sayonara o Aritgato (1989), Suki Suki Daisuki (1990), all one volume, and Merii-san no Hijitsu (1991-1992), five volumes, in Margaret.
Kamio began Boys Over Flowers in 1992, also in Margaret. The series was a big hit in Japan, spawning thirty-six volumes by 2003. She also published a few short stories relating to Boys Over Flowers, which would lead to the release of the thirty-seventh volume in 2008. Boys Over Flowers remains Kamio's most popular series to date with several different adaptations on many platforms. She also won the 41st Shogakukan Manga Award for the series in the shojo category.
She began her series, Cat Street in Bessatsu Margaret in August 2004. The series ended in October 2007, after eight volumes. An additional chapter of the manga was published in 2008 to commemorate the release of the television drama adaptation.
Yoko Kamio broke into the shōnen genre with her series, Matsuri Special in Jump Square magazine. Matsuri Special ended in 2009 with four volumes. She returned to Bessatsu Margaret shortly after with her series, Tora to Okami, which went on for six volumes.
Her most recent series are Ibara no Kanmuri (2013-2014) in Bessatsu Margaret and Boys Over Flowers Season 2 in Shonen Jump+.
- Ano Hi ni Aitai (あの日に逢いたい; 1989)
- Sayonara o Arigatō (さよならをありがとう; 1989)
- Suki Suki Daisuki (スキスキ大好き; 1990)
- Merii-san no Hijitsu (めりーさんの羊; 1991-1992; 5 volumes)
- Boys Over Flowers (1992-2003; 37 volumes)
- Cat Street (2004-2007; 8 volumes)
- Matsuri Special (2008-2009; 4 volumes)
- Tora to Okami (2009-2012; 6 volumes)
- Ibara no Kanmuri (2013-2014; 2 volumes)
- Boys Over Flowers Season 2 (2015-present)