Riichiro Inagaki is a Japanese manga writer born in Tokyo on June 20, 1976. His career began after he worked as an animation assistant at a manga and film production company. He made his professional debut as a writer in October 2001 with a one-shot published in Shogakukan’s Big Comic Spirits magazine, followed by several other short works.

Inagaki’s first major success came with the football manga Eyeshield 21. After winning a storyboard award, he collaborated with artist Yusuke Murata on the series, which was serialized in Shueisha’s Weekly Shōnen Jump from July 2002 to June 2009. The series was collected in 37 tankōbon volumes and later adapted into a 145-episode anime television series. During the production of the anime, Inagaki established Kome Studio, a copyright management company intended to help protect the rights of original manga creators.

Following the conclusion of Eyeshield 21, Inagaki continued to work on several collaborative projects. In June 2010, he published Kiba&Kiba with artist Bonjae in Weekly Shōnen Jump. He also worked with artist Katsunori Matsui on Shinpai Kato No Face for Weekly Young Jump and the two-chapter series Alpha Centauri Dōbutsuen for Jump X. In August 2015, he published the one-shot Kobushi Zamurai in Big Comic Superior with artist Ryoichi Ikegami.

In March 2017, Inagaki began his next major series, Dr. Stone, in Weekly Shōnen Jump, with illustrator Boichi. The series concluded in 2022, with its chapters collected in 27 tankōbon volumes. Dr. Stone received the 64th Shogakukan Manga Award for best shōnen manga in 2019. The series was adapted into a multiple-season anime, with its fourth season, Dr. Stone: Science Future, beginning in 2025. In December 2020, Inagaki launched another series, Trillion Game, in Big Comic Superior, again collaborating with artist Ryoichi Ikegami; the series concluded in 2025.

Throughout his career, Inagaki has primarily worked as a writer in collaboration with illustrators. He has described his own strengths as lying in storytelling and conceptual thinking rather than drawing. In interviews, he has noted that his childhood interest in science influenced his approach to Dr. Stone, and he has expressed a desire to move away from traditional portrayals of protagonists with superhuman strength, instead focusing on the power of knowledge and ingenuity. In 2006, he served alongside Akira Toriyama and Eiichiro Oda as a committee member for the Tezuka Award, a semi-annual manga award presented by Shueisha.