Ron Perlman as Hellboy

Selma Blair as Elizabeth 'Liz' Sherman

Doug Jones as Abraham 'Abe' Sapien

John Hurt as Prof. Trevor 'Broom' Bruttenholm

Rupert Evans as John Myers

Jeffrey Tambor as Tom Manning

Ladislav Beran as Karl Ruprecht Kroenen

Bridget Hodson as Ilsa Haupstein

Karel Roden as Grigori Rasputin

Brian Steele as Sammael

Corey Johnson as Agent Clay

Kevin Trainor as Young 'Broom'

Brian Caspe as Agent Lime

James Babson as Agent Moss

Stephen Fisher as Agent Quarry

Garth Cooper as Agent Stone

Angus MacInnes as Sgt. Whitman

Jim Howick as Cpl. Matlin

Mark Taylor as Truck Driver

Daniel Aarsman as Kid

Bettina Ask as Kid

Álvaro Navarro as Kid

Emilio Navarro as Kid

Rory Copus as Kid on Rooftop

Tara Hugo as Doctor Jenkins

Richard Haas as Second Doctor

Andrea Miltner as Doctor Marsh

Jo Eastwood as Down's Patient

Charles Grisham as Museum Guard

Jan Holíček as Museum Guard

Jeremy Zimmermann as Lobby Guard

Monty L. Simons as Orderly

Pavel Cajzl as Sherpa Guide

Andrea Stuart as Girl with Kittens

William Hoyland as General Klaus Werner von Krupt

Millie Wilkie as Young Liz

Bob Sherman as Television Host

Ellen Savaria as Blonde Television Reporter

Petr Sekanina as German Scientist

Aleš Košnar as German Scientist

Justin Svoboda as Young Guy

Winter Ave Zoli as Girlfriend

Santiago Segura as Train Driver

Albert Moy as Train Driver

David Hyde Pierce as Abe Sapien (voice) (uncredited)

Helene Maksoud as Liz Sherman's Mother (uncredited)

Guillermo del Toro as Guy Dressed as Dragon (uncredited)

Mike Mignola as Knight (uncredited)

Miroslav Lhotka as Museum Guard (uncredited)

Michael Lindsay as Security Guard (voice) (uncredited)

Todd Kramer as Radioman (uncredited)