Manabu Muraji is a Japanese actor and voice actor born on October 24, 1963, in Hyogo Prefecture, Japan. He began his career in 1986 after joining the Bungakuza theatre company's training institute, becoming a full company member in 1991. While his early work included on-screen appearances in television dramas and films, he gradually shifted his focus to voice acting. In 2021, he completed a doctoral program in Music Culture Studies at Seitoku University, earning a Ph.D..

In anime, Muraji often lends his voice to mature, authoritative, or paternal figures. One of his earlier anime roles was Itou in the 2002 series Saikano: Another Love Song. He has taken on several significant antagonist and supporting roles. He voiced Kyosuke Mamo, a time-traveling scientist and adversary of Lupin III, in the 2018 television special Lupin the Third: Is Lupin Still Burning?. In the 2020 science fiction mystery series ID: INVADED, he portrayed Takuhiko Hayaseura, the enigmatic chief of the secret organization Kura and the story's main antagonist. He voiced the elderly but formidable former knight Salman in the 2021 original adventure anime Fena: Pirate Princess. In 2022, he took on the role of Loki Helios in the fantasy series Lucifer and the Biscuit Hammer. His other anime credits include roles in long-running franchises such as a Donquixote Family member in One Piece, and appearances in series like Natsume's Book of Friends, The Saint's Magic Power is Omnipotent, and the 2025 figure skating anime Medalist.

Beyond anime, a substantial part of Muraji's voice career is dedicated to dubbing foreign films and television series, known as fukikae. He is the regular Japanese voice for actor Clark Gregg, most famously dubbing his character Phil Coulson from the Marvel Cinematic Universe films and the television series Agents of S.H.I.E.L.D.. Another notable role is providing the Japanese voice for Andrew Scott's portrayal of Jim Moriarty in the BBC series Sherlock. His dubbing work also includes voicing Merry Brandybuck in The Lord of the Rings film trilogy and characters in projects like Disney's Zootopia.