Takafumi Yamaguchi is a Japanese voice actor born on June 13, 1977, in Fukuoka Prefecture, Japan. He is a graduate of the voice actor training school affiliated with Mouse Promotion, an agency he has been associated with throughout his career. Prior to his time with Mouse Promotion, he was also affiliated with the agency Stardas-21.

Yamaguchi's career encompasses voice work in anime, video games, and Japanese dubs of foreign films and television series. His professional debut is marked by his role as Shinji Tanaka in the 2005 Sega game Yakuza. In anime, he is perhaps best known for voicing the character Pluto in the 2008 series Black Butler, a role mentioned in connection with the series Black Butler: His Butler, Performer. The same year, he also contributed voices to episodes of Gintama and the series Monochrome Factor. One of his earlier anime roles was Junpei Nitta in the 2006 series Futari wa Pretty Cure Splash Star.

Beyond these prominent credits, Yamaguchi has been active in dubbing international productions into Japanese. Notable examples include providing the Japanese voice for the character Adam in the series Lab Rats and for Jackson in Zoe Valentine. His film dubbing work from the mid-2000s includes numerous projects such as the Japanese-language DVD versions of Jasmine Blossoms, The Prince Who Turned into a Frog, and Four Sisters Story. In video games, his role in Yakuza remains a key credit, and he also participated in Super Robot Wars Z in 2008.

Known for his versatility, Yamaguchi has built a career playing a wide range of supporting characters across different media, demonstrating an ability to adapt to various styles and genres.