Mathias Kozlowski is a French actor and voice director, born on April 22, 1972, in Toulouse, France. He began his career in dubbing in 1985 with the film The Goonies, working under the direction of Jenny Gérard. He studied at the École des enfants du spectacle and later at the Lycée Montaigne in Paris. Beyond his work as a voice actor, he taught event programming and C++ at the EFREI engineering school for six years.

Kozlowski is widely recognized for his voice work in animation. He is the regular French voice of Fred Jones in the Scooby-Doo franchise, a role he has held since 1999 across numerous films and television series, including Quel scoop, Scooby-Doo! and various direct-to-video animated movies. He also voices Robin in the Teen Titans series and its spin-off, Teen Titans Go!. In the world of anime, he is known for voicing the protagonist Tsubasa Ōzora in the 2018 remake of the series Captain Tsubasa. Another notable anime role is providing the voice of Shotaro Kaneda in the French dub of the landmark film Akira. His other voice work includes roles in the animated films South Park: Bigger, Longer & Uncut, Dofus: Book 1 - Julith, and various films in the DC Universe Animated Original Movies, frequently as Nightwing.

In addition to his animation work, Kozlowski has an extensive career dubbing live-action film and television. He is a regular voice for actors Cillian Murphy, Walton Goggins, and Scott Foley. Some of his notable live-action dubbing credits include providing the French voice for Johnny Depp in Benny & Joon, Edward Norton in Primal Fear, Leonardo DiCaprio in The Quick and the Dead, and Philip Seymour Hoffman in Capote. He also dubbed the voice of Jamie Bamber as Lee "Apollo" Adama in the reimagined Battlestar Galactica series. His work as a voice director is also noted, contributing to the French adaptations of various productions.