 Debi DerryberryJames 'Jimmy' Isaac Neutron (voice) | James 'Jimmy' Isaac Neutron (voice) |
 Megan CavanaghJudy Neutron / VOX (voice) | Judy Neutron / VOX (voice) |
 Mark DeCarloHugh Neutron / Pilot / Arena Guard (voice) | Hugh Neutron / Pilot / Arena Guard (voice) |
 Jeffrey GarciaSheen Estevez (voice) | Sheen Estevez (voice) |
 Patrick StewartKing Goobot V (voice) | King Goobot V (voice) |
 Martin ShortOoblar (voice) | Ooblar (voice) |
 Frank WelkerGoddard / Poultra (voice) | Goddard / Poultra (voice) |
 Rob PaulsenCarl Wheezer / Mr. and Mrs. Wheezer / Kid in Classroom (voice) | Carl Wheezer / Mr. and Mrs. Wheezer / Kid in Classroom (voice) |
 Carolyn LawrenceCindy Vortex (voice) | Cindy Vortex (voice) |
 Crystal ScalesLibby Folfax (voice) | Libby Folfax (voice) |
 Candi MiloNick Dean / Britney / PJ (voice) | Nick Dean / Britney / PJ (voice) |
 David L. LanderYokian Guard / Gus (voice) | Yokian Guard / Gus (voice) |
 Carlos AlazraquiMr. Estevez (voice) | Mr. Estevez (voice) |
 Jim CummingsUltra Lord / Mission Control / General Bob (voice) | Ultra Lord / Mission Control / General Bob (voice) |
| KKeith AlcornBobby / Kid / Control Yokian (voice) | Bobby / Kid / Control Yokian (voice) |
 Kimberly BrooksZachary / Reporter / Angie / Libby's Mom (voice) | Zachary / Reporter / Angie / Libby's Mom (voice) |
 Andrea MartinMs. Winfred Fowl (voice) | Ms. Winfred Fowl (voice) |
 Billy WestBobby's Twin Brother (voice) / Butch (voice) / Jailbreak Cop (voice) / Old Man Johnson (voice) / Robobarber (voice) / Flurp Announcer (voice) / Yokian Officer (voice) / Anchor Boy (voice) / Guard (voice) | Bobby's Twin Brother (voice) / Butch (voice) / Jailbreak Cop (voice) / Old Man Johnson (voice) / Robobarber (voice) / Flurp Announcer (voice) / Yokian Officer (voice) / Anchor Boy (voice) / Guard (voice) |
 Mary HartYokian Newscaster #2 (voice) | Yokian Newscaster #2 (voice) |
 Bob GoenYokian Newscaster #1 (voice) | Yokian Newscaster #1 (voice) |
 Dee Bradley BakerNorad Officer (voice) | Norad Officer (voice) |
 Laraine NewmanHostess (voice) | Hostess (voice) |
 John A. DavisOctapuke Kid / Guard / Bennie (voice) | Octapuke Kid / Guard / Bennie (voice) |
 Paul GreenbergGuard (voice) | Guard (voice) |
| MMark MenzaYokian Incubator Operator (voice) | Yokian Incubator Operator (voice) |
 Jeannie EliasLittle Girl / Camera Person (voice) | Little Girl / Camera Person (voice) |
 Michael HagiwaraChris (voice) | Chris (voice) |
| RRichard AllenDigital Voice (voice) | Digital Voice (voice) |
| BBrian CapshawScreamer (voice) | Screamer (voice) |
| CCheryl RayScreamer (voice) | Screamer (voice) |
