Paul Giamatti as Harvey Pekar

Hope Davis as Joyce Brabner

Judah Friedlander as Toby Radloff

James Urbaniak as Robert Crumb

Earl Billings as Mr. Boats

James McCaffrey as Fred

Maggie Moore as Alice Quinn

Vivienne Benesch as Lana

Daniel Tay as Young Harvey

Harvey Pekar as Real Harvey

Donal Logue as Stage Actor Harvey

Josh Hutcherson as Robin

Joyce Brabner as Joyce Brabner

Molly Shannon as Stage Actor Joyce

Toby Radloff as Toby Radloff

Eytan Mirsky as Guitarist

Joey Krajcar as Batman

Chris Ambrose as Superman

Cameron Carter as Green Lantern

Mary Faktor as Housewife

Madylin Sweeten as Danielle

Ebon Moss-Bachrach as MTV Director