Kiyomitsu Mizuuchi is a Japanese voice actor affiliated with the talent management firm Ken Production. He was born on November 17, 1960, and began his career in the industry in 1993. Over the decades, he has built a substantial body of work, lending his voice to a wide array of characters in anime, video games, and dubbed foreign films.

Mizuuchi is frequently cast in supporting and character roles, often portraying authority figures, military officers, and mature men. This is exemplified by several of the roles noted by the user. In the Attack on Titan OVA series Lost Girls, he provided the voice for the character Stratmann. He also voiced the role of Staden in the 2018 series The Legend of the Galactic Heroes: Die Neue These, a strategic commander within the Galactic Empire. His work also includes the role of Spidermatsumoto in the quirky series Yoshimoto Muchikko Monogatari and the character Gensai in The Last Kunoichi, demonstrating the range of projects he has been involved in.

Beyond these specific credits, his filmography is extensive and diverse. He has appeared in long-running and internationally renowned series such as Cowboy Bebop, Naruto, and various installments of the Mobile Suit Gundam franchise, including Mobile Suit Gundam SEED. In the psychological sci-fi series Ergo Proxy, he voiced the character Iggy, a self-aware robot, showcasing his ability to bring complex, non-human characters to life. More recently, he has been cast in series like The Fable in 2024 and City the Animation in 2025.

A significant portion of Mizuuchi's career is dedicated to the art of Japanese dubbing for foreign films and television series. He has become a regular voice for American actor Frank Grillo, dubbing his performances as Brock Rumlow in multiple Marvel Cinematic Universe films, including Captain America: The Winter Soldier, Captain America: Civil War, and Avengers: Endgame. His other notable dubbing roles include Dr. Alexander Isaacs in the Resident Evil film series, Drift in Transformers: Age of Extinction, and characters in major Hollywood productions such as Interstellar and Logan. This extensive work in dubbing highlights his versatility and his ability to match the performances of a wide range of international actors.