Frank Welker
Megatron (voice) (67 eps)
Josh Keaton
Jack Darby (voice) (66 eps)
Peter Cullen
Optimus Prime (voice) (65 eps)
Jeffrey Combs
Ratchet (voice) (65 eps)
Tania Gunadi
Miko Nakadai (voice) (65 eps)
Kevin Michael Richardson
Bulkhead (voice) (65 eps)
Ernie Hudson
Agent William Fowler (voice) (65 eps)
Andy Pessoa
Rafael "Raf" Esquivel (voice) (65 eps)
Sumalee Montano
Arcee (voice) (65 eps)
Steve Blum
Starscream (voice) (65 eps)
Daran Norris
Knock Out (voice) (65 eps)
David Sobolov
Shockwave (voice) (14 eps)
Nolan North
Smokescreen (voice) (13 eps)
Michael Ironside
Ultra Magnus (voice) (13 eps)
Adam Baldwin
Breakdown (voice) (11 eps)
Clancy Brown
Silas (voice) (8 eps)
Tony Todd
Dreadwing (voice) (8 eps)
Gina Torres
Airachnid (voice) (8 eps)
Markie Post
June Derby (voice) (7 eps)
John Noble
Unicron (voice) (4 eps)
Peter Mensah
Predaking (voice) (4 eps)
Alexandra Krosney
Sierra (voice) (3 eps)
George Takei
Alpha Trion (voice) (2 eps)
David Kaye
Hardshell (voice) (2 eps)
James Horan
Wheeljack (voice) (1 eps)
Richard Green
Skyquake (voice) (1 eps)
Dwayne Johnson
Cliffjumper (voice) (1 eps)
Will Friedle
Bumblebee (voice) (1 eps)
Billy Brown
Cliffjumper (voice) (1 eps)
Reggie Bannister
Museum Security Guard (voice) (1 eps)
Brad Raider
Vince (voice) (1 eps)
John DiMaggio
Vogel (voice) (1 eps)
Robert Forster
General Bryce (voice) (1 eps)