Aaron is a fictional character from the comic book series The Walking Dead and television series of the same name. He is portrayed by Ross Marquand in the television series.

In both media, he acts as a recruiter for the Alexandria Safe-Zone located in Washington, D.C., for Rick Grimes and his fellow survivors on the road. Although initially mistrusted by Rick's group, he gradually gains their trust and becomes a respected and resourceful ally to the group. Aaron is the longest surviving Alexandria character and is notable for being the comic book's first openly gay character.

Aaron is introduced as a recruiter for the Alexandria Safe-Zone, a community built from a quarantine zone for politicians during the outbreak. Aaron comes into contact with Rick's group shortly after they exterminated the Hunters and had been observing them with his fellow recruiter and boyfriend Eric to determine if they were suitable for the community. Although the survivors are initially suspicious of Aaron's motives, they go along with him to Washington, D.C., and eventually join Alexandria. The leader of Alexandria, Douglas Monroe, is hesitant about the prospect of the group staying, but Aaron defends them, believing they are genuinely good people. He remains fiercely loyal to Rick and company for the remainder of the series.

After the group's arrival, Eric is stabbed by a random woman they were trying to recruit. Eric is taken back to Alexandria by Aaron and is quickly healed by the town's surgeon, Denise Cloyd. In the wake of this event, the couple mutually decides to stop recruiting and focus on maintaining things within the safety of their walls. A zombie attack puts the community in disarray and culminates in Rick becoming leader in the wake of Douglas' death. Aaron and Eric are both assigned inventory together and keep track of the community's rations and supplies to ensure that it continues to run properly. The two also participate in training with Rick and the rest of the group in order to defend themselves better against the undead. Aaron and Eric begin to grow more comfortable venturing outside the walls again, assisting others in supply runs.

A recruiter named Paul "Jesus" Monroe finds Alexandria and offers an alliance with the nearby community of the Hilltop Colony. Aaron convinces Rick to trust Jesus and not make an enemy out of him, reminding Rick of how he didn't initially trust Aaron when he came to rescue the group. The alliance leads to joining Hilltop's conflict with an extortionist group called the Saviors, led by Negan. The conflict begins with the death of Abraham. Aaron and Eric are both shaken, with the two of them attending his memorial service. They later participate in the war against the Saviors and form the Militia, an army consisting of many members from Alexandria, Hilltop Colony, and another community called The Kingdom. Eric is killed in battle, leaving Aaron devastated. His grief quickly turns into fury and he vows to kill every remaining Savior in order to avenge Eric's death. The Militia wins the war and Negan is sentenced to life in prison.

Two years later, Aaron has moved on from Eric's death but struggles with the idea of finding new love. He continues to be a productive member of Alexandria by leading zombie herds away from the communities. Aaron considers starting a relationship with Jesus, but he is unsure due to his continued grief over Eric and Jesus' casual relationship with Hilltop nurse, Alex. Aaron is later attacked by the Whisperers, a cult of primitivists that wear the faces of the dead, and is stabbed by Beta. He is taken to Hilltop to recover. During his stay at Hilltop, he gets closer to Jesus and the two begin a relationship. As the Whisperers burn down Hilltop, Aaron manages to rescue Rick's son Carl, despite his injuries. Aaron and Jesus return to Alexandria and aid them against the Whisperer's undead army. Andrea is bitten in the attack and Aaron and Jesus give their condolences before she dies. When on the road returning to Hilltop, Aaron and Jesus are ambushed by Beta and his last few remaining Whisperer followers. In the ensuing fight, Aaron shoots Beta, killing him and officially ending the Whisperers.

The communities make contact with a civilization in Ohio called The Commonwealth. While they initially help in the rebuilding of the communities, they occupy the Coalition and enforce their capitalistic rule. A class war breaks out within The Commonwealth. Aaron and Jesus join the civilians against the Commonwealth Army. Rick manages to deescalate the riot and calls for peace, but is later shot and killed by the Governor's son, Sebastian Milton. Aaron and Jesus grieve Rick along with the others that knew him. Twenty-five years later, Aaron and Jesus continue to be in a relationship and live on a riverside farm where an adult Carl, his wife Sophia, and their daughter, Andrea, visit frequently.

Prior to the events of the series Aaron became a recruiter for the Alexandria Safe-Zone, along with his boyfriend Eric. At some point Aaron recruited a group of three led by Davidson, who Aaron believed would be a good addition to the community. However, Davidson's violent nature led to Deanna exiling him. Aaron, Aiden and Nicholas were forced to escort Davidson's group out, taking all their weapons and leaving them only a few days worth of supplies.