- Shuhei Nomura (Daily Lives of High School Boys) as Kikuma Todo, Teiichi's underhanded classmate and childhood friend
- Ryoma Takeuchi (Kamen Rider Drive) as Dan Otaka, Teiichi's naturally charismatic classmate
- Shotaro Mamiya (Ushijima the Loan Shark The Final) as Roland Himura, the student favored to be the next student council president
- Kotaro Yoshida (Assassination Classroom) as Josuke Akaba, Teiichi's father, and an alumnus at Teiichi's Kaitei High School
- Mei Nagano (Rurouni Kenshin) as Mimiko Shiratori, Teiichi's secret friend
- Jun Shison (Ressha Sentai ToQGer) as Komei Sakahibara, Teiichi's right-hand man
- Yudai Chiba (Tensou Sentai Goseiger) as Okuto Morizono, a member of the shogi club
Based on Usamaru Furuya's manga of the same name, the film follows Teiichi Akaba, a high school student and his student government struggles at a private boys' school in Showa Era Japan. Directed by Akira Nagai (Sekai Kara Neko ga Kieta Nara) with script by Yoshihiro Izumi (live-action Death Note, anohana).
Teiichi no Kuni is set for an April 29, 2017 release in Japan.