 | Ron Perlman als Hellboy (voice) |
 | Selma Blair als Liz Sherman (voice) |
 | John Hurt als Professor Trevor 'Broom' Bruttenholm (voice) |
 | Doug Jones als Abe Sapien (voice) |
 | Peri Gilpin als Professor Kate Corrigan (voice) |
 | J. Grant Albrecht als Oliver Trombolt (voice) |
 | Jim Cummings als Tom Manning (voice) |
 | Grey DeLisle als Anna / Harpy-Hag #2 (voice) |
 | Rob Paulsen als Sydney Leach / Anna's Fiance (voice) |
 | Kath Soucie als Erzsebet Ondrushko (voice) |
 | DeeDee Rescher als Harpy-Hag #1 (voice) |
 | Cree Summer als Hecate (voice) |
 | James Arnold Taylor als Young Broom / Father Lupescu (voice) |
| Lawrence Gordon | Executive Producer |
| Lloyd Levin | Executive Producer |
| Guillermo del Toro | Creative Producer |
| Mike Mignola | Characters |
| Mike Mignola | Story |
| Mike Mignola | Consulting Producer |
| Mike Mignola | Comic Book |
| Mike Richardson | Executive Producer |
| Victor Cook | Director |
| Tad Stones | Director |
| Tad Stones | Story |
| Tad Stones | Additional Writing |
| Tad Stones | Supervising Producer |
| Stephen R. Brown | Executive Producer |
| Morris Berger | Executive Producer |
| John W. Hyde | Executive Producer |
| Kevin Hopps | Screenplay |
| Christopher Drake | Music |
| Sidney Clifton | Executive Producer |
| Scott D. Greenberg | Executive Producer |
| Michael Wolf | Executive Producer |
| Matt Steinauer | Editor |
| Scott Hemming | Executive Producer |
| Stephanie Elliott | Producer |
