Characters as they appeared in, and characters exclusive to or making their debut in, the 2003 4Kids-produced TMNT cartoon. For tropes relating to characters who originally appeared in other incarnations or were created here and went on to appear elsewhere, please visit the [[Characters/TeenageMutantNinjaTurtles franchise character page]].

[[index]]
* [[Characters/TeenageMutantNinjaTurtles2003TurtlesAndSplinter The Turtles and Splinter]]
* [[Characters/TeenageMutantNinjaTurtles2003Allies Allies]]
* [[Characters/TeenageMutantNinjaTurtles2003FootClan The Foot Clan]]
** [[Characters/TeenageMutantNinjaTurtles2003TheShredder The Shredder]]
* [[Characters/TeenageMutantNinjaTurtles2003Other Other Characters]]
* [[Characters/TeenageMutantNinjaTurtles2003BattleNexus The Battle Nexus]]
* [[Characters/TeenageMutantNinjaTurtles2003NinjaTribunalArc The Ninja Tribunal Arc]]
* [[Characters/TeenageMutantNinjaTurtles2003FastForward Fast Forward]]
[[/index]]

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