Yoshisada Sakaguchi was a Japanese actor and voice actor born in Tokyo on October 2, 1939. He was a graduate of the Faculty of Letters at Hokkaido University. In 1963, he joined the Bungakuza Acting Institute and became an official member of the Bungakuza theater company in 1967, where he built a career in theater, television, and voice acting. In addition to his performance work, he served as a professor at J. F. Oberlin University and was later named a professor emeritus. He also took on the role of director at the Bungakuza Acting Institute in 2011.

Sakaguchi contributed his voice to numerous animated works across several decades. In the early 1990s, he voiced Alexis in the film Hashire Melos! and Commander Exxegran Giri in Super Dimensional Fortress Macross II: The Movie. He played Ghim in the Record of Lodoss War OVA series and Briareos Hecatombcales in the Appleseed film. In 1999, he took on the role of Hachiroh Tohbe, who also serves as the narrator, in the film Jin-Roh: The Wolf Brigade. He voiced Colonel Karel Ranke in the Monster television series and had a role in the Mushi-Shi anime. In film, he portrayed Tonpetti in JoJo's Bizarre Adventure: Phantom Blood, Tilin in The Tibetan Dog, and the Great Grandfather in A Letter to Momo. His later credits include a role as Strydum in the 2018 Baki anime series.

Beyond anime, Sakaguchi was widely recognized for his work in dubbing foreign films and series. He was the regular Japanese voice for actors Morgan Freeman, Sean Connery, and Tommy Lee Jones. His extensive dubbing credits include providing the voice for Red in The Shawshank Redemption, Detective Somerset in Seven, and Lucius Fox in Batman Begins for Morgan Freeman, as well as characters in films like The Rock, The Untouchables, and the Men in Black series for other actors.

Yoshisada Sakaguchi passed away on February 13, 2020, due to colorectal cancer at the age of 80. His final voice role was recorded in October 2019 for a dubbed version of the film The Poison Rose.