Logan Lerman
Percy Jackson

Brandon T. Jackson
Grover Underwood

Alexandra Daddario
Annabeth Chase

Douglas Smith
Tyson

Leven Rambin
Clarisse La Rue

Jake Abel
Luke Castellan

Katelyn Mager
Young Thalia

Grey Damon
Chris Rodriguez

Paloma Kwiatkowski
Thalia Grace

Anthony Stewart Head
Chiron

Stanley Tucci
Mr. D / Dionysus

Nathan Fillion
Hermes

Robert Maillet
Polyphemus / Laistrygonian

Ron Perlman
Polyphemus (voice)

Connor Dunn
Tereus

Alisha Newton
Young Annabeth

Bjorn Yearwood
Young Grover

Samuel Braun
Young Luke

Mary Birdsong
Gray Sister #1

Yvette Nicole Brown
Gray Sister #2

Missi Pyle
Gray Sister #3

Octavia Spencer
Martha (voice)

Christopher Redman
Reardon

Jordan Weller
Ichneutae

Camille Atebe
Harpy Barista

Anthony Shim
Barista - Hecatonshire

Robert Knepper
Kronos

Richard Yearwood
Ganymede

Derek Mears
Cyclops #1

Aleks Paunovic
Cyclops #2

Maxine Miller
Parcel Store Customer

Shohreh Aghdashloo
Oracle (voice)

Craig Robinson
George (voice)