Karl Diedrich Bader (born December 24, 1966, in Alexandria, Virginia) is an American actor and voice actor. His voice roles related to Hanna-Barbera include:
- Uncle Evan on What's New, Scooby-Doo?
- Brad Adams in Scooby-Doo! Mask of the Blue Falcon
- Hoss Delgado and Fiskerton in Cartoon Network Universe: FusionFall
- Diedrich Bader at the Internet Movie Database