Issei Takahashi is a Japanese actor and voice actor born on December 9, 1980, in Tokyo, Japan. He began his career in entertainment as a child actor, joining a children's theater group at the age of ten at the encouragement of his family. His first involvement in a film was a small role in the 1990 movie Hoshi wo Tsugumono.

Takahashi made his debut as a voice actor in 1995 while still a junior high school student. He successfully auditioned for a role in a Studio Ghibli production and was cast as Seiji Amasawa in the acclaimed animated film Whisper of the Heart. In this coming-of-age story, he provided the Japanese voice for Seiji, a boy around 14 to 15 years old who is an aspiring violin maker and becomes a key figure in the protagonist's journey of self-discovery. This role marked his only major, widely recognized credit specifically for anime voice acting. Notably, Takahashi experienced his voice change shortly after completing the recording for the film.

Following his voice acting debut and throughout his career, Takahashi's primary focus has been on live-action performance in television, film, and theater. He has appeared in numerous television dramas, including several NHK taiga dramas such as Genroku Ryoran, Shinsengumi, and Gunshi Kanbei. His work in the 2015 comedy drama Min-owon him critical acclaim and his first major acting awards, including the日剧学院赏 for Best Supporting Actor. He has continued to build a prolific career in live-action, with notable roles in series like Quartet and the film Shin Godzilla. While he has received multiple awards for his live-action acting, his voice acting achievements remain primarily associated with his debut role in Whisper of the Heart.