Starring

• Andrew Lincoln as Rick Grimes, the series' protagonist, the father of Carl and Judith, and a former sheriff's deputy, who recently relinquished his leadership over the survivor group out of disgust towards his own previous actions as leader.
• Norman Reedus as Daryl Dixon, an antihero-like Southern redneck, who is also the group's primary hunter and has a strong bond with Carol, and later forms a bond with Beth.
• Steven Yeun as Glenn Rhee, a former pizza delivery man married to Maggie Greene, who has matured over the series.
• Lauren Cohan as Maggie Greene, Hershel's elder daughter, Beth's half-sister, and Glenn's wife, who is a determined, fierce and capable fighter.
• Chandler Riggs as Carl Grimes, Rick's adolescent son. Brave to a fault, Carl begins to develop a callous mentality in response to the lethal landscape of a savage, new world. However he is also emotionally conflicted with himself because of the brutality of his previous choices in the new world.
• Danai Gurira as Michonne, a quiet and meticulous, yet fierce woman, who has recently joined Rick's group. She has begun to bond with the group, and shares a close bond with Rick's son Carl but is still fierce and secretive of her past.
• Melissa McBride as Carol Peletier, a former victim of domestic abuse, who has empowered herself but has come to make several dark and questionable decisions for the good of her group. She is the only known female Atlanta camp survivor left.
• Scott Wilson as Hershel Greene, a religious former veterinarian and farmer, who is protective of his daughters. He maintains his faith despite many tragic events and acts as the group's primary moral compass as well as a surrogate father figure to Rick and Glenn.
• David Morrissey as The Governor, the former leader of the now-abandoned Woodbury and a primary threat to the prison community, and the primary antagonist of the first half of the season, who is now calling himself "Brian Heriot". Having become alarmed of his cold ways he is attempting to redeem himself by caring for a family he encounters.

Also starring

• Emily Kinney as Beth Greene, a soft-spoken teenage girl, Hershel's younger daughter, and Maggie's younger half-sister. Beth has become emotionally numb but is secretly still emotionally fragile, and later forms a bond with Daryl.
• Chad L. Coleman as Tyreese Williams, Sasha's peace-keeping older brother and one of the few survivors of Woodbury and Karen's boyfriend.
• Sonequa Martin-Green as Sasha Williams, Tyreese's younger sister, who is seemingly fiery, ruthless and cold but deep down is a compassionate young woman. She has also developed an attraction to Bob.
• Lawrence Gilliard Jr. as Bob Stookey, a former army medic, who struggles to recover from alcoholism. He also develops an attraction to Sasha.

The Prison

• Brighton Sharbino as Lizzie Samuels, a young girl, who has joined the prison community and suffers from psychological problems and obsessed with walkers.
• Kyla Kenedy as Mika Samuels, Lizzie's younger sister, who has also joined the prison community.
• Sunkrish Bala as Dr. Caleb Subramanian, a doctor, who has joined the prison community and is more commonly known as "Dr. S".
• Luke Donaldson as Luke, a young boy, who has joined the prison community.
• Sherry Richards as Jeanette, a former Woodbury resident, who has joined the prison community.
• Vincent Martella as Patrick, a young teenager, who has joined the prison community.
• Melissa Ponzio as Karen, Tyreese's new love interest and the lone survivor of the Woodbury army massacre.
• Kennedy Brice as Molly, a young girl, who develops a friendship with Lizzie, Mika, and Luke.
• Victor McCay as Ryan Samuels, Lizzie and Mika's father.
• Kyle Gallner as Zach, a survivor, who has joined the prison community and forms a relationship with Beth.

Chambler family

• Alanna Masterson as Tara Chambler, a police academy attendee, who was surviving with her family before encountering The Governor.
• Audrey Marie Anderson as Lilly Chambler, a former nurse, Meghan's mother, and Tara's sister, who develops a relationship with The Governor.
• Danny Vinson as David Chambler, is the father of Tara and Lily and the grandfather of Meghan who suffers from terminal cancer.
• Meyrick Murphy as Meghan Chambler, Lilly's daughter, who begins to see The Governor as a father figure.

Martinez's camp

• Jose Pablo Cantillo as Caesar Martinez, one of The Governor's most trusted allies, who leads a new group of survivors.
• Kirk Acevedo as Mitch Dolgen, a former tank operator, who has joined Martinez's new group.
• Juliana Harkavy as Alisha, a former member of the army reserves, who forms a relationship with Tara.
• Enver Gjokaj as Pete Dolgen, a member of Martinez's group and Mitch's brother.

Abraham's group

• Michael Cudlitz as Sgt. Abraham Ford, a former soldier trying to get Eugene to Washington, D.C. so he can stop the outbreak.
• Christian Serratos as Rosita Espinosa, a young Hispanic woman, who is Abraham's girlfriend.
• Josh McDermitt as Dr. Eugene Porter, a scientist, who claims to know what caused the outbreak and is being escorted by Abraham and Rosita to government officials in Washington, D.C.

The Claimers

• Jeff Kober as Joe, leader of a small group of heavily armed marauders called the "Claimers", who live by the philosophy of "claiming" and the primary antagonist of the second half of the season.
• Davi Jay as Tony, a right-hand of Joe and member of Joe's group.
• Marcus Hester as Len, a hostile member of Joe's group, who forms an antagonism with Daryl.
• Keith Brooks as Dan, a sexually deviant of Joe's group.
• Scott Dale as Lou, a member of Joe's group, the first one who faces Rick.
• J. D. Evermore as Harley, a member of Joe's group.
• Eric Mendenhall as Billy, a ruthless member of Joe's group.

Terminus

• Denise Crosby as Mary, a resident of Terminus, who greets survivors that arrive there.
• Andrew J. West as Gareth, the mysterious leader of Terminus.
• Tate Ellington as Alex, a member of Terminus.

Miscellaneous

• Kerry Condon as Clara, a mysterious woman Rick encounters in the forest.
• Robin Lord Taylor as Sam, a survivor encountered by Rick and Carol.
• Brina Palencia as Ana, a survivor traveling with Sam, who is encountered by Rick and Carol.
• Aldis Hodge as Mike, Michonne's former boyfriend, who appears in a flashback.
• Brandon Fobbs as Terry, Michonne's former friend, who appears in a flashback.

Lennie James was initially reported to return as Morgan Jones, Rick's first human encounter in the apocalypse,^[15] however showrunner Scott M. Gimple confirmed that he would not appear in the fourth season, saying that he was misquoted. Despite this, Gimple stated that Morgan would return in later seasons.^[16] Morgan eventually returned in the series' fifth season.