Demon Slayer: Kimetsu no Yaiba – The Movie: Infinity Castle (Japanese: 劇場版 鬼滅の刃 無限城編, Hepburn: Gekijō-ban Kimetsu no Yaiba: Mugen-jō-hen), also known simply as Demon Slayer: Infinity Castle, is an upcoming Japanese animated dark fantasy action film based on the "Infinity Castle" arc of the 2016–20 manga series Demon Slayer: Kimetsu no Yaiba by Koyoharu Gotouge. It is a direct sequel to the fourth season of the anime television series as well as its fourth film adaptation, following Demon Slayer: Kimetsu no Yaiba – The Movie: Mugen Train (2020), Demon Slayer: Kimetsu no Yaiba – To the Swordsmith Village (2023), and Demon Slayer: Kimetsu no Yaiba – To the Hashira Training (2024) The film is directed by Haruo Sotozaki and written by Ufotable staff members.

Unlike the Swordsmith Village and Hashira Training adaptations, which are compilation films, Infinity Castle is a feature-length film adaptation due to the arc's content and dramatic pacing, similarly to Mugen Train. The film was first announced on June 2024, immediately following the airing of the fourth season's finale, as the first installment of a three-part film series.

Demon Slayer: Kimetsu no Yaiba – The Movie: Infinity Castle is scheduled to be released in Japan on July 18, 2025, by Aniplex and Toho.