Pete Davidson

Marmaduke (voice)

J.K. Simmons

Zeus (voice)

David Koechner

Phil Winslow (voice)

Mary Hart

EntertainMutt Tonight Host (voice)

Julie Nathanson

Dottie Winslow (voice)

Terri Douglas

Billy Winslow (voice)

Erin Fitzgerald

Barbara Winslow (voice)

Stephen Stanton

King Tut (voice)

Brian Hull

Guy Hilton (voice)

Sumalee Montano

Amy (voice)

Andrew Morgado

Henri / Phillipe (voice)

Chris Hackney

Announcer (voice)