is a Japanese manga series written and illustrated by Kouji Miura. It has been serialized in Shueisha's Weekly Shà Ânen Jump since April 2021, with its chapters collected in 24 volumes as of February 2026. An anime television series adaptation produced by TMS Entertainment and animated by Telecom Animation Film aired from October 2024 to March 2025. A second season animated by Electric Circus is set to premiere in October 2026.
The series focuses on Taiki Inomata, a student at Eimei Junior and Senior High, an athletics-oriented school, where he is a member of the boys' badminton team and is considered simply average. Every morning, he trains to get better early in the gym, often at the same time and place as his upperclasswoman Chinatsu Kano, the star of the girls' basketball team. Taiki quickly develops a crush on her, but is initially too shy to speak to her despite their continual alone time together. His fortunes change, however, when Chinatsu moves in with Taiki's family after her parents leave Japan to work abroad. With Chinatsu now living with him, Taiki aims to slowly develop his relationship with her as they both strive to make it to the national championship with their respective teams.
Written and illustrated by Kouji Miura, Blue Box began its serialization in Shueisha's manga magazine Weekly Shà Ânen Jump on April 12, 2021, after the one-shot version had been published on August 3, 2020. Shueisha has collected its chapters into individual volumes. The first volume was released on August 4, 2021. As of February 4, 2026, 24 volumes have been released.
Blue Box has been licensed for simultaneous publication in North America as it is released in Japan, with its chapters being digitally launched by Viz Media on its Shonen Jump website. Shueisha also simulpublishes the series in English for free on the Manga Plus app and website. In February 2022, Viz Media announced that they had licensed the series in print format; the first volume was released on November 1 of the same year. The manga is also licensed in Indonesia by Elex Media Komputindo.
An anime television series adaptation was announced in November 2023. Planned and produced by TMS Entertainment, it is animated by Telecom Animation Film and directed by Yà «ichirà  Yano, with handling series composition and designing the characters. The series aired for two consecutive cours from October 3, 2024, to March 27, 2025, on TBS and its affiliates. For the first cours, the opening theme is "Same Blue" by Official Hige Dandism, and the ending theme is by Eve; for the second cours, the opening theme is by , and the ending theme is by Tomoo. Netflix licensed the series and is streaming it worldwide.
A second season was announced immediately following the airing of the finale episode of the first season, with Daisuke Sakà  taking over as director and animated by Electric Circus. It is set to premiere on TBS on October 4, 2026.
In August 2021, the first volume of the manga had over 170,000 copies in circulation in less than a week after its release. By October 2025, the manga had over 9 million copies in circulation.
In June 2021, Blue Box was nominated for the seventh Next Manga Award in the Best Print Manga category; it placed eighth out of 50 nominees, but won the Global Prize. The series ranked fourth on the Nationwide Bookstore Employees' Recommended Comics of 2022.
Blue Box received critical acclaim. Anthony Gramuglia of Comic Book Resources (CBR) stated, "Blue Box is a sentimental story about human connection. It's beautifully drawn, at times resembling a manga more than a typical . If Blue Box continues, it will likely become an earnest, sincere entry in Shà Ânen Jumps romantic catalog". Timothy Donohoo of CBR compared Blue Box to Kenta Shinohara's Witch Watch and Shigure Tokita's Don't Blush, Sekime-san! due to both series having concepts and romantic aspects similar to Blue Boxs.