Sopravvissuti della sezione centrale del volo Oceanic Airlines 815

Jack Shephard	-	Matthew Fox
Kate Austen	-	Evangeline Lilly
James "Sawyer" Ford	-	Josh Holloway
Charlie Pace	-	Dominic Monaghan
Claire Littleton	-	Emilie de Ravin
Aaron Littleton	-	William Blanchette
Sayid Jarrah	-	Naveen Andrews
Hugo "Hurley" Reyes	-	Jorge Garcia
Boone Carlyle	-	Ian Somerhalder
Shannon Rutherford	-	Maggie Grace
John Locke	-	Terry O'Quinn
Michael Dawson	-	Harold Perrineau Jr.
Walter "Walt" Lloyd	-	Malcolm David Kelley
Sun-Hwa Kwon	-	Yunjin Kim
Jin-Soo Kwon	-	Daniel Dae Kim
Rose Nadler	-	L. Scott Caldwell
Nikki Fernandez	-	Kiele Sanchez
Paulo	-	Rodrigo Santoro
Leslie Artz	-	Daniel Roebuck
Edward Mars	-	Fredric Lehne
Neil "Frogurt"	-	Sean Whalen
Seth Norris	-	Greg Grunberg

Sopravvissuti della sezione di coda del volo Oceanic 815

Ana Lucia Cortez	-	Michelle Rodriguez
Mr. Eko	-	Adewale Akinnuoye-Agbaje
Bernard Nadler	-	Sam Anderson
Libby Smith	-	Cynthia Watros
Cindy Chandler	-	Kimberley Joseph

Abitanti dell'isola prima dell'incidente aereo

Danielle Rousseau	-	Mira Furlan
Desmond Hume	-	Henry Ian Cusick
Jacob	-	Mark Pellegrino
Nemesi di Jacob	-	Titus Welliver

Gli Altri

Benjamin Linus	-	Michael Emerson
Juliet Burke	-	Elizabeth Mitchell
Mikhail Bakunin	-	Andrew Divoff
Richard Alpert	-	Nestor Carbonell
Alexandra Rousseau	-	Tania Raymonde
Tom Friendly	-	M.C. Gainey
Ethan Rom	-	William Mapother
Goodwin Stanhope	-	Brett Cullen
Danny Pickett	-	Michael Bowen
Colleen Pickett	-	Paula Malcolmson
Karl Martin	-	Blake Bashoff
Bea Klugh	-	April Grace
Isabel	-	Diana Scarwid

Membri del Progetto DHARMA

Roger Linus	-	Jon Gries
Horace Goodspeed	-	Doug Hutchison
Amy Goodspeed	-	Reiko Aylesworth
Olivia Goodspeed	-	Samantha Mathis
Kelvin Joe Inman	-	Clancy Brown
Pierre Chang	-	François Chau
Annie	-	Madeline Carroll
Stuart Radzinsky	-	Eric Lange

Equipaggio del cargo Kahana

Naomi Dorrit	-	Marsha Thomason
Daniel Faraday	-	Jeremy Davies
Miles Straume	-	Ken Leung
Charlotte Staple Lewis	-	Rebecca Mader
Frank Lapidus	-	Jeff Fahey
George Minkowski	-	Fisher Stevens
Regina	-	Zoë Bell
Martin Keamy	-	Kevin Durand
Capitano Gault	-	Grant Bowler

Sopravvissuti del volo Ajira 316

Ilana Verdansky	-	Zuleikha Robinson
Bram	-	Brad William Henke
Caesar	-	Saïd Taghmaoui

Personaggi nei flash

Christian Shephard	-	John Terry
- Jack (Bambino)	-	John O'Hara
- Ray Shephard	-	Raymond J. Barry
- Margo Shephard	-	Veronica Hamel
- Sarah Shephard	-	Julie Bowen
- David Shephard	-	Dylan Minnette
- Achara	-	Bai Ling
Charles Widmore	-	Alan Dale
- Penelope Widmore	-	Sonya Walger
- Charlie Hume	-	Marvin DeFreitas
Carole Littleton	-	Susan Duerden
- Lindsey Littleton	-	Gabrielle Fitzpatrick
Eloise Hawking	-	Fionnula Flanagan
Matthew Abaddon	-	Lance Reddick
Anthony Cooper	-	Kevin Tighe
Mary Ford	-	Susse Budde
Sam Austen	-	Lindsey Ginter
- Diane Janssen	-	Beth Broderick
- Wayne Janssen	-	James Horan
- Kevin Callis	-	Nathan Fillion
Cassidy Phillips	-	Kim Dickens
- Clementine Phillips	-	Olivia Vickery
Noor "Nadia" Abed Jazeem	-	Andrea Gabriel
- Padre di Sayid	-	Sayed Bedreya
- Omer Jarrah	-	Xavier Raabe-Manupule
Tito Reyes	-	Archie Ahuna
- David Reyes	-	Cheech Marin
- Carmen Reyes	-	Lillian Hurst
- Dave	-	Evan Handler
- Leonard Simms	-	Ron Bottitta
- Johnny	-	DJ Qualls
- Diego Reyes	-	Derrick Bulatao
- Lisa Reyes	-
Helen Norwood	-	Katey Sagal
Woo-Jung Paik	-	Byron Chung
Jae Lee	-	Tony Lee
Yemi	-	Adetokumboh M'Cormack
Liam Pace	-	Neil Hopkins
- Simon Pace	-	John Henry Canavan
- Megan Pace	-	Sammi Davis
- Karen Pace	-	Vanessa Branch
- Megan Pace	-