List of Ben 10 characters

Voiced by:

• Tara Strong – Ben 10, Ben 10: Secret of the Omnitrix, Ben 10: Ultimate Alien (as 10 years old in "Forge Of Creation"), Ben 10: Omniverse (11 years old), and Ben 10 (2016) and various commercials, shorts and video games[3]
• Yuri Lowenthal – Ben 10: Alien Force, Ben 10: Ultimate Alien, Ben 10: Omniverse and Ben 10 (2016) (as an elderly Ben in "The 11th Alien: Part 1" and as the teenage Bens in "Alien X-Tinction"), various commercials and video games[3]

Portrayed by:

• Graham Phillips – Ben 10: Race Against Time
• Ryan Kelley – Ben 10: Alien Swarm

Benjamin Kirby "Ben" Tennyson (alias "Ben 10") is the main protagonist of the franchise and wielder of the Omnitrix, a powerful watch-like device allowing him to turn into many different aliens. He is the cousin of Gwen Tennyson and best friend of Kevin Levin.

Voiced by:

• Meagan Smith – Ben 10
• Ashley Johnson – Ben 10: Alien Force, Ben 10: Ultimate Alien, and Ben 10: Omniverse
• Montserrat Hernandez – Ben 10 (2016)

Portrayed by:

• Haley Ramm – Ben 10: Race Against Time
• Galadriel Stineman – Ben 10: Alien Swarm

Gwendolyn "Gwen" Tennyson is Ben's paternal cousin and Kevin's love interest, a skilled sorceress who inherited her magical "spark" from her Anodite grandmother, Verdona.

Voiced by:

• Paul Eiding – Ben 10, Ben 10: Alien Force, Ben 10: Ultimate Alien, and Ben 10: Omniverse
• Adam Wylie – Ben 10 (as a kid in "Don't Drink the Water")
• Jason Marsden – Ben 10: Ultimate Alien (as a young adult in "Moonstruck")
• David Kaye – Ben 10 (2016)

Portrayed by:

• Lee Majors – Ben 10: Race Against Time
• Barry Corbin – Ben 10: Alien Swarm

Maxwell "Max" Tennyson is a retired Plumber and the paternal grandfather of Ben and Gwen.

Voiced by:

• Michael Reisz – Ben 10 (in the episode "Kevin 11")
• Charlie Schlatter – Ben 10 (in later episodes)
• Greg Cipes – Ben 10: Alien Force, Ben 10: Ultimate Alien, Ben 10: Omniverse, and Ben 10 (2016)

Portrayed by:

• Nathan Keyes – Ben 10: Alien Swarm

Kevin Ethan Levin is an Osmosian, a mutant subspecies of human, who first appeared as one of Ben's enemies. However, he later reformed and is now his friend and Gwen's love interest.

Voiced by:

• Bumper Robinson – Ben 10: Omniverse

Rook Blonko is a Revonnahgander Plumber from the planet Revonnah, who serves as Ben's partner throughout Omniverse after Gwen and Kevin leave the team. He has advanced combat knowledge and wields the multi-purpose Proto-Tool.

Voiced by: David McCallum

Professor Paradox is a character who debuts in Alien Force and later appears in Ultimate Alien and Omniverse. Following a lab accident, he was displaced from space and time for millennia, eventually gaining complete understanding and control over it. Unable to remember his original name, he took the moniker "Professor Paradox".

Voiced by:

• Robert David Hall – Ben 10, Ben 10: Secret of the Omnitrix, Ben 10: Destroy All Aliens
• Jeff Bennett – Ben 10: Alien Force, Ben 10: Ultimate Alien
• René Auberjonois – Ben 10: Omniverse
• David Kaye – Ben 10 (2016)

Azmuth, also known as the "First Thinker", is a Galvan scientist and creator of the Omnitrix as well as the sword Ascalon. He is a recurring ally to Ben, in spite of being asocial and apathetic.

Voiced by:

• Steve Blum - Ben 10 (2005) and Ben 10: Omniverse

• James Remar - Ben 10: Alien Force and Ben 10: Ultimate Alien

• Yuri Lowenthal - Ben 10 (2016)

Vilgax is a Chimera Sui Generis warlord from the planet Vilgaxia, and the archenemy of Ben. His main goal is to obtain the Omnitrix to rule the universe using an army of droids equipped with its transformation abilities. He is additionally served by an army of robot henchmen and the alien Psyphon.

In the reboot continuity, Vilgax is Azmuth's former assistant, who stole the Omnitrix from him and used it for universal conquest. However, Azmuth managed to drain half of Vilgax's DNA and put it into the Omnitrix, leaving him powerless until he recovered his full power from Ben years later.

Voiced by:

• Kari Wahlgren - Ben 10 (2005), Ben 10: Alien Force, Ben 10: Ultimate Alien, Ben 10: Omniverse

• Tara Strong - Ben 10 (2016)

Charmcaster, real name Hope, is a sorceress from the magical dimension of Ledgerdomain who was raised by her uncle, Hex, after her father Spellbinder was killed by the villain Addwaitya. Though primarily an antagonist, she has occasionally taken on a more neutral or anti-heroic role.

In the reboot continuity, Charmcaster is a normal human, named Heather, whose magic is derived from one of Hex's spellbooks.

Voiced by:

• Khary Payton - Ben 10 (2005), Ben 10: Alien Force, Ben 10: Ultimate Alien, Ben 10: Omniverse
• Robin Atkin Downes - Ben 10 (2016)

Hex is Charmcaster's uncle, whom she has a strained relationship with, though they do genuinely care for each other. Initially introduced as a villain, he later reformed offscreen and became a teacher at Friedkin University as of Omniverse.

In the reboot continuity, Hex is established to be at least 10,000 years old, having regularly restored his youth and powers using special pools of light.