Nahoko Uehashi is a Japanese writer and cultural anthropologist born in Tokyo on July 15, 1962. She graduated from Rikkyo University and completed a master's degree at the same institution before earning a PhD in cultural anthropology. Her doctoral research focused on the Yamatji, an indigenous Aboriginal people of Australia, and she conducted extensive fieldwork in Western Australia. Uehashi worked as a full-time professor of cultural anthropology at Kawamura Gakuen Women's University and was named a professor emeritus in 2025. Her academic background in anthropology and ethnology deeply informs her approach to world-building and character development in her fiction.

Uehashi began her writing career in 1989 with the novel Seirei no ki (The Sacred Tree), published while she was still a graduate student. She is best known for several major fantasy series that have been adapted into anime and manga. The Moribito series, which began with Seirei no moribito (Guardian of the Spirit) in 1996, is among her most celebrated works. This series follows Balsa, a female bodyguard and spear-wielder who protects a young prince. The first volume received the Noma Children's Literature New Face Prize and the Sankei Children's Culture and Publishing Award. The Moribito series has been adapted into a twenty-six episode anime television series produced by Production I.G and directed by Kenji Kamiyama, which aired in 2007. The series also inspired a manga adaptation, a radio drama, and a live-action television series.

Uehashi wrote Kemono no soja (The Beast Player) as a two-volume novel in 2006, later expanding it to four volumes in 2009. This story follows Erin, a young girl who becomes a caretaker of mythical creatures called Beast-Lords. The series was adapted into a fifty-episode anime titled The Beast Player Erin, which aired on NHK Educational TV beginning in 2009. The Beast Player also received a manga adaptation illustrated by Moto Takezaki, which began serialization in Monthly Shonen Sirius in 2008. The novel series was published in English as two volumes, The Beast Player and The Beast Warrior, with the latter receiving a Michael L. Printz Award Honor in 2020.

Uehashi authored the Shika no o (The Deer King) novel series, first published in 2014. The story centers on Van, a former soldier who survives a mysterious plague carried by wild dogs and escapes from a salt mine with a young girl named Yuna. The novels won the Japan Booksellers Award and the Japan Medical Fiction Award in 2015. The Deer King was adapted into an animated film produced by Production I.G, directed by Masashi Ando and Taku Kishimoto, and released in Japanese cinemas in February 2022. The film was screened at the Annecy International Animation Film Festival in June 2021. The Deer King has also been adapted into a manga series.

Several manga adaptations of Uehashi's work exist. Moribito II: Guardian of the Darkness was released as a manga, continuing the story of Balsa as she returns to her homeland of Kanbal to clear the name of her mentor. The Beast Player received its manga adaptation as noted above. Jin ~Anime Seirei no Moribito Gaiden~ is a manga spinoff related to the Moribito anime. Additionally, the Moribito series has been adapted into multiple manga versions, including a serialization in Monthly Shonen Sirius.

Recurring themes in Uehashi's work draw directly from her training as a cultural anthropologist. Her stories frequently explore the coexistence of humans with nature and spiritual beings, the relationship between different cultures and peoples, and the challenges faced by marginalized individuals living between defined societies. She has stated that her grandmother's folktales about the coexistence of humans and animals became the root of her imagination for creating fantasy worlds. Uehashi often constructs protagonists who are strong female figures, such as the warrior Balsa, or young people who must navigate complex relationships with animals and authority. She has expressed a deliberate rejection of coming-of-age stories that portray growing up as a process of loss, instead seeking to show that adults are admirable because of their maturity and ability to protect others.

Uehashi has received numerous awards for her contributions to children's literature and fantasy. In 2014, she won the Hans Christian Andersen Award, the highest international recognition for a children's author. Her English translations have been honored by the American Library Association, with Moribito: Guardian of the Spirit winning the Mildred L. Batchelder Award in 2009 and Moribito II: Guardian of the Darkness receiving a Batchelder Honor in 2010. She has also received the Noma Children's Literature Award, the Sankei Children's Culture and Publishing Award, the Japan Booksellers Award, and the Kikuchi Kan Prize in 2024. Her books have sold more than 11.5 million copies in Japan and have been translated into English, German, French, Italian, Portuguese, Spanish, Swedish, Korean, and Mandarin.