He is married to fellow Japanese voice actress Hitomi Oikawa since 1988.
He is best known for his roles as Vegeta from the Dragon Ball series, Reinhard von Lohengramm from Legend of the Galactic Heroes, Andromeda Shun from Saint Seiya, Heiji Hattori from Detective Conan, and Captain Falcon in the Super Smash Bros. series.
Horikawa started out as a child actor in elementary school.
He made his debut in voice acting as Kenta Hirono, the protagonist of the 1984 anime Dream Soldier Wing-Man.
From there, he became famous for his anime character roles as Andromeda Shun (Saint Seiya), Reinhard von Lohengramm (Legend of the Galactic Heroes), Vegeta (Dragon Ball series), and Heiji Hattori (Detective Conan).