Logan Lerman
Percy Jackson
Brandon T. Jackson
Grover Underwood
Alexandra Daddario
Annabeth Chase
Leven Rambin
Clarisse La Rue
Katelyn Mager
Young Thalia
Grey Damon
Chris Rodriguez
Paloma Kwiatkowski
Thalia Grace
Anthony Stewart Head
Chiron
Stanley Tucci
Mr. D / Dionysus
Robert Maillet
Polyphemus / Laistrygonian
Ron Perlman
Polyphemus (voice)
Alisha Newton
Young Annabeth
Bjorn Yearwood
Young Grover
Mary Birdsong
Gray Sister #1
Yvette Nicole Brown
Gray Sister #2
Octavia Spencer
Martha (voice)
Christopher Redman
Reardon
Camille Atebe
Harpy Barista
Anthony Shim
Barista - Hecatonshire
Maxine Miller
Parcel Store Customer
Shohreh Aghdashloo
Oracle (voice)
Craig Robinson
George (voice)