Jim Carrey as Tom Popper

Carla Gugino as Amanda

Angela Lansbury as Mrs. Van Gundy

Ophelia Lovibond as Pippi

Madeline Carroll as Janie Popper

Clark Gregg as Nat Jones

Jeffrey Tambor as Mr. Gremmins

David Krumholtz as Kent

Philip Baker Hall as Franklin

Maxwell Perry Cotton as Billy Popper

James Tupper as Rick

Dominic Chianese as Reader

William Charles Mitchell as Yates

Henry Kelemen as Young Tommy Popper

Kelli Barrett as Tommy's Mom

Dylan Clark Marshall as Young Tommy Popper #2

Brian T. Delaney as Young Tom Popper, Sr. (voice)

Elaine Kussack as Gremmins's Secretary

Harlin C. Kearsley as Town Car Driver

Desmin Borges as Daryl

Lee Moore as Reginald

Dominic Colón as Tito

Jeff Lima as Freddy

Frank Ciornei as Klaus

J.R. Horne as Arnold

Matthew Wolf as Antarctic Friend (voice)

Andrew Stewart-Jones as Animal Control Guy

James Chen as Fish & Game Officer

Rafael Osorio as Marine & Waterfowl Officer

Curtis Shumaker as Sanitation Officer

Joseph D'Onofrio as Random Man on Street

Olga Merediz as Nanny

Betsy Aidem as Tavern Hostess

Angel Caban as Fishmonger

Chris Beetem as Young Developer

Charles L. Campbell as Old Tom Popper, Sr. (voice)

Daniel Stewart Sherman as Zoo Security Guard

Mike Massimino as Cop #1

Charlie Semine as Cop #2 (Quint)

Cynthia Kirchner as Pulse Lounge Beautiful Girl (uncredited)