Kōsuke Sakaki is a Japanese male actor and voice actor. He was born on May 19, 1964, in Nagano Prefecture, Japan. He is affiliated with the agency Kera-ke Production. He stands 176 centimeters tall. He is known for providing the Japanese dub voice for the character Mika in the anime series Lycoris Recoil and its related film Lycoris Recoil: Friends are thieves of time. He also voiced the role of Sōichirō Kataoka in the series Idol Memories.

Sakaki moved to Tokyo to pursue a career in theater. He dropped out of university shortly after enrolling and went on to train at the Literary Theater’s attached drama institute as part of its 26th class. He also studied at the Theater Group Subaru’s attached institute, completing its 13th class, before making his professional debut. He was formerly a member of the agency D-Color. His hobbies include watching movies, riding motorcycles, and making his own films.

His career in voice work spans numerous television anime series, films, and video games. In 2014, his early anime roles included a Mob character and a Viper in Garo: The Animation, and Gold in Tribe Cool Crew. In 2015, he appeared in several series, including a role as a Vice Captain in Tokyo Ghoul √A, Asano in The Testament of Sister New Devil, and a supporting role in Lupin the Third (New Series).

In 2016, he voiced the character Sōichirō Kataoka in Idol Memories. He also played a Company President in ViVid Strike! and an Elder of the Springrain faction in Gintama. In 2017, he appeared as a Teacher in Akashic Records of Bastard Magic Instructor, as Yoshimasa Yagisawa in the film The Anthem of the Heart, and as a Crew Member in Black Butler: Book of the Atlantic. His roles in 2018 included Karaha Shogyo in Basilisk: The Ouka Ninja Scrolls and Getto Hachiya in Megalo Box.

In 2020, Sakaki voiced the character Makoto Kobe in the anime series Wave, Listen to Me! He returned to the role of a senior executive in the sequel series NOMAD: Megalo Box 2 in 2021. That same year, he voiced the role of Selim in Lupin the Third Part 6. His role as Mika in Lycoris Recoil in 2022 became a prominent credit. In 2023, he voiced the character Erepha in the series Adventure in the Kingdom of Ania and the father of a character named Ai in Dark Gathering. In 2024, he voiced the character Big D in the web anime series Ninja Kamui.

Sakaki has also contributed to several animated films. His filmography includes a role as a member of the Tetsuryu-kai in Lupin the Third: Goemon Ishikawa's Spray of Blood (2017), the father of a character named Jun in The Stranger by the Beach (2020), and an unspecified role in The First Slam Dunk (2022).

In the field of video games, he provided the Japanese voice for the characters Silver Mains and John Parman in the 2021 release Resident Evil Village. In 2024, he voiced the character Robert Katze in the game A Certain Magical Index: Imaginary Fest.

He has also worked extensively in dubbing foreign films and television series. Notable dubbing roles include Qin Ming in the Chinese series The Water Margin (2013), the character Face in the Japanese dub of Justice League (2017), and Jin Kyeong-hoon in the Korean series Hellbound (2021), portrayed by actor Yang Ik-june. In 2023, he voiced a character named Abat in the Star Wars: Visions Volume 2 short The Song of the Abyssal Plain.